Angelo Marcello TARANTINO - personale UniMoRe

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Angelo Marcello TARANTINO

Professore Ordinario
Dipartimento di Ingegneria "Enzo Ferrari"

Pubblicazioni

- Fibre in polipropilene per calcestruzzi strutturali fibrorinforzati [Brevetto]
Tarantino, Angelo Marcello; Nobili, Andrea
abstract

fibre sintetiche per calcestruzzi

2024 - Large twisting of non-circular cylinders in unconstrained elasticity [Articolo su rivista]
Falope, Federico; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with the equilibrium problem of non-circular cylinders subjected to finite torsion. A three-dimensional kinematic model is formulated, where, in addition to the rigid rotation of the cross sections, the large twist of the cylinder also generates in- and out-of-plane pure deformation of the cross sections and the variation of the cylinder length. Following the semi-inverse approach, the displacement field prescribed by the above kinematic model contains an unknown constant, which governs the elongation of the cylinder, and three unknown functions which describe the pure deformation of the cross sections. A Lagrangian analysis is then performed and the compressible Mooney-Rivlin law is assumed for the stored energy function. Once evaluated the Piola-Kirchhoff stresses, the boundary value problem is formulated. Nevertheless, the governing equations assume a coupled and nonlinear form which does not allow to apply standard solution methods. Therefore, the unknown functions are expanded into power series using polynomial terms in two variables. These series contain unknown constants which are evaluated applying the iterative Newton's method. With this procedure an accurate semi-analytical solution has been obtained, which can be used to compute displacements, stretches and stresses in each point of the cylinder. For the elliptical and rectangular sections, the results provided by the proposed solution method are shown by a series of graphs. Finally, the Poynting effect was investigated by varying the section shape of the cylinder.

2024 - Shot-Earth as Sustainable Construction Material: Chemical Aspects and Physical Performance [Articolo su rivista]
Barbieri, Luisa; Lanzoni, Luca; Marchetti, Roberta; Iotti, Simone; Tarantino, Angelo Marcello; Lancellotti, Isabella
abstract

Soil has long been one of the most widely used building materials globally. The evolution of soil-based construction materials has seen steady improvement over the centuries, even as traditional materials have given way to newer options like reinforced concrete. Nonetheless, soil-based construction has maintained its relevance and, in recent decades, has garnered increased attention due to sustainability concerns and renewed research interest. Among the innovative earth-based materials, shot-earth (SE) stands out as one of the most advanced. Research on SE has facilitated efficient handling of soil variability in mix design and provided structural engineers with relevant models for dimensioning and detailing reinforced SE constructions. This paper focuses on studying the durability characteristics of various types of SE to ascertain their ability to withstand environmental degradation over their intended lifespan. The tests conducted indicate that SE can serve as a viable construction material in numerous real-life scenarios, offering a sustainable alternative to existing materials.

2024 - Structural design of reinforced earthcrete (ReC) beams [Articolo su rivista]
Franciosi, M.; Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, Marco
abstract

This paper presents the results of an extensive experimental campaign aimed at evaluating the feasibility of using steel-reinforced earthen materials for load-bearing structural applications, with a focus on a new category termed "shot-earth". Addressing excavated soil, a major source of construction waste, shot-earth demonstrates remarkable properties, such as notable green strength and reduced water sensitivity. The experimental program includes four-point bending tests on steel-reinforced shot-earth beams, along with pull-out tests to assess the adherence between ribbed steel bars and shot-earth. A flexural design approach, traditionally suited for reinforced concrete, is presented and validated to establish a reliable model for reinforced shot-earth elements in bending state. These findings suggest that leveraging existing models for reinforced concrete can overcome some traditional challenges associated with earth-based constructions, promoting them as a viable and ecological alternative to conventional construction materials.

2023 - A strain energy function for large deformations of compressible elastomers [Articolo su rivista]
Pelliciari, M.; Sirotti, S.; Tarantino, A. M.
abstract

Elastomers are typically considered incompressible or slightly compressible. However, we present simple tension and bulk tests showing that, under large deformations, these materials can undergo significant volume changes. A review of the literature reveals the lack of an accurate hyperelastic model for finite volumetric deformations of elastomers. Therefore, we propose a new volumetric strain energy density (SED) that overcomes the limitations of the current models. The main advantages of the proposed SED are: (1) accurate description of the response of rubbers for both small and large volumetric deformations; (2) ability to reproduce diverse behaviors during volume shrinkage and expansion; (3) adaptability to other compressible materials, such as soft tissues, foams and hydrogels. Using the deviatoric- volumetric split of the strain energy, the proposed volumetric SED is combined with a suitable deviatoric part selected from the literature. The parameters of the combined SED are calibrated by fitting the model to the experimental data from simple tension and bulk tests. As a result, an accurate description of the response of elastomers under both shape and volume deformations is provided. The proposed SED can be implemented in numerical codes to capture the effects of volumetric deformations on the equilibrium solutions for various stress states.

2023 - Analytical pressure–deflection curves for the inflation of pre-stretched circular membranes [Articolo su rivista]
Sirotti, S.; Pelliciari, M.; Aloisio, A.; Tarantino, A. M.
abstract

2023 - Changing the approach to sustainable constructions: An adaptive mix-design calibration process for earth composite materials [Articolo su rivista]
Franciosi, M.; Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

One major drawback of excavation earth-based composite construction materials is the variability in excavation earth characteristics from site to site. This variability can affect certain physical properties, and, in turn, the design models used to create a structure. To solve this problem, a methodology has been developed to predict the physical properties of earth-based composites for any mix-design variation, which enables a robust structural design process. This new methodology has been tested for Shot-earth, a new class of earth-based composite material made using high rates of excavation earth, aggregates, and a low rate of stabilization if needed. Shot-earth is placed using a high-speed dry-mix process. The methodology was tested by preparing small, inexpensive specimens through a process that simulates the dry-process used to fabricate Shot-earth in the field. An adaptive technique, used in conjunction with the experimental methodology, allows for the identification of the variant of possible Shot-earth mix-designs that provides optimal physical properties for a specific project. This technique is potentially applicable to any type of earth-based composite. The proposed methodology’s reliability enables a fast and cost-effective detailing of Shot-earth constructions.

2023 - Finite element solution of vibrations and buckling of laminated thin plates in hygro-thermal environment based on strain gradient theory [Articolo su rivista]
Bacciocchi, M.; Fantuzzi, N.; Luciano, R.; Tarantino, A. M.
abstract

The paper aims to develop a finite element methodology to deal with vibrations and buckling of laminated thin plates subjected to thermal and hygroscopic effects, once a second-order strain gradient theory is included to overcome the limitations of conventional elasticity and to capture nonlocal phenomena. The numerical scheme takes advantage of Hermite approximation for both membrane and bending primary variables, since the strain gradient introduces higher-order derivatives of the nodal displacements. Its versatility is proven by dealing with general lamination schemes and arbitrary boundary conditions. The analyzed configurations cannot be solved analytically.

2023 - Shot-Earth: A Material for Structural Engineering [Capitolo/Saggio]
Savino, V.; Franciosi, M.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

2023 - The Challenge of Designing a New Class of Earth-Based Composites Able to Increase the Circularity and Sustainability of the Construction Market [Capitolo/Saggio]
Savino, V.; Franciosi, M.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

2023 - Theoretical and experimental analysis of the von Mises truss subjected to a horizontal load using a new hyperelastic model with hardening [Articolo su rivista]
Pelliciari, Matteo; Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

The von Mises truss has been widely studied in the literature because of its numerous applications in multistable and morphing structures. The static equilibrium of this structure was typically addresses by considering only geometric nonlinearities. However, Falope et al. (2021) presented an entirely nonlinear solution in finite elasticity and demonstrated that material nonlinearities play an important role in the prediction of both snap-through and Euler buckling. In such work, the von Mises truss was subjected to a vertical load and thus the system was symmetric and the deformations were relatively small. The present contribution extends the investigation to the case of a horizontal load, which is much more complex due to asymmetry and very large deformations. Since most rubbers employed in technological applications exhibit hardening under large stretches, we propose a new hyperelastic model capable of reproducing this behavior. The advantage of such model compared to the ones available in the literature is that the equilibrium solution maintains a straightforward mathematical form, even when considering compressibility of the material. In addition, in this work we present a new formulation in nonlinear elasticity to predict Euler buckling. The formulation takes into account shear deformation. The analytical prediction agrees well with both finite element (FE) and experimental results, thus demonstrating the accuracy of the proposed model.

2022 - A Continuum Model for Circular Graphene Membranes Under Uniform Lateral Pressure [Articolo su rivista]
Pelliciari, M; Tarantino, Am
abstract

Despite the numerous applications of pressurized graphene membranes in new technologies, there is still a lack of accurate mechanical models. In this work we develop a continuum model for circular graphene membranes subjected to uniform lateral pressure. We adopt a semi-inverse method by defining a simplified kinematics of deformation and we describe the material behavior with a stored energy function that takes into account both nonlinearity and anisotropy of graphene. An expression of the applied pressure as a function of the deflection of the membrane is obtained from an approximate solution of the equilibrium. The simplifying hypotheses of the analytical model are verified by a finite element (FE) analysis in nonlinear elasticity. In addition, a numerical solution of the differential equilibrium equations of the exact theory is presented. The pressure-deflection response from FE and numerical solutions agree well with the prediction of the analytical formula, demonstrating its accuracy. The analytical solution is then employed for the response of a two-layered composite membrane made of graphene deposited onto a soft substrate. This application is of great interest since new nanotechnologies make use of layered nanocomposites. Differently from our entirely nonlinear approach, most continuum models in the literature are based on the assumption of linear elastic material, which is suitable only when deformations are small. The present work gives a comprehensive description of the mechanics of pressurized graphene membranes.

2022 - A cohesive-based FE interface for concrete members retrofitted with ultra performance cementitious mortars [Abstract in Atti di Convegno]
Savino, V; Lanzoni, L.; Tarantino, Am; Viviani, M
abstract

2022 - A continuum model for graphene in nonlinear elasticity and its green applications [Abstract in Atti di Convegno]
Pelliciari, Matteo; Tarantino, Angelo Marcello; Lanzoni, Luca
abstract

2022 - An Auto-Calibrating Semi-Adiabatic Calorimetric Methodology for Strength Prediction and Quality Control of Ordinary and Ultra-High-Performance Concretes [Articolo su rivista]
Viviani, Marco; Lanzoni, Luca; Savino, Vincenzo; Tarantino, Angelo Marcello
abstract

A timely knowledge of concrete and ultra-high-performance concrete (UHPC) strength is possible through the so-called strength-equivalent time (Et) curves. A timely knowledge of concrete strength is useful, for instance, to precisely determine when the shores of a hardening structural element can be safely removed. At the present time, the preparation of the strength-Et curves requires time-consuming and labor-intensive testing prior to the beginning of construction operations. This paper proposes an innovative method to derive the strength-Et and total heat-Et curves for both normal strength and UHPC. Results confirmed that the proposed method is fast, inexpensive, self-calibrating, accurate and can detect any variation of the concrete mix proportions or components quality. In addition, the quality of predictions of strength–maturity curves can be constantly improved as the specimens’ population increases. Finally, results obtained with the proposed method were compared with those obtained using standard methods, showing a good agreement.

2022 - Analytical and experimental study of snap-through instability in truss structures [Abstract in Atti di Convegno]
Pelliciari, Matteo; Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

Abstract

2022 - Analytical, numerical and experimental study of the finite inflation of circular membranes [Articolo su rivista]
Pelliciari, M.; Sirotti, S.; Aloisio, A.; Tarantino, A. M.
abstract

In the present work we derive an analytical expression for the pressure–deflection curve of circular membranes subjected to inflation. This problem has been studied mostly from a numerical point of view and there is still a lack of accurate closed-form solutions in nonlinear elasticity. The analytical formulation is developed with a semi-inverse method by setting a priori the kinematics of deformation of the membrane. A compressible Mooney–Rivlin material model is considered and a pressure–deflection relation is derived from the equilibrium. The kinematics is approximated and therefore the obtained solution is not exact. Consequently, the formulation is adjusted by introducing an additional polynomial function in the pressure–deflection equation. The polynomial is calibrated by fitting numerical solutions of the exact system of differential equilibrium equations. The calibration is done over a wide range of constitutive parameters that covers the response of all rubber materials for technological applications. As a result, a definitive and accurate expression of the applied pressure as a function of the deflection of the membrane is obtained. The formula is validated with finite element (FE) simulations and compared with other solutions available in the literature. The comparison shows that the present model is more accurate. In addition, unlike the other models, it can be applied to compressible materials. Experimental uniaxial and bulge tests are carried out on rubber materials and the model proposed is used to characterize the Mooney–Rivlin constitutive parameters. Since the pressure–deflection formula is accurate and easy-to-use, it is an innovative tool in engineering applications of inflated membranes.

2022 - Damage-Based Hysteresis Bouc-Wen Model for Reinforced Concrete Elements [Relazione in Atti di Convegno]
Sirotti, S.; Pelliciari, M.; Briseghella, B.; Tarantino, A. M.
abstract

2022 - Experimental characterization and predictive modeling of the flexural behavior of HPFRC/UHPFRC beams [Abstract in Atti di Convegno]
Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

The high manufacturing costs of UHPFRC applications together with time-consuming tests re- quested for the characterization and control quality restrict a wider application of this kind of smart material in the field of the rehabilitation of concrete structures. For this purpose, predictive strength models are useful to reduce this kind of and, at the same time, optimize the amount of compounds in the mixture according to the design requirements, for example by detecting the minimal dosage of fibers necessary to attain the design tensile strength. At the present, no predictive strength models suitable for HPFRC/UHPFRC are available. This work proposes a model able to predict the mechanical response of HPFRC/UHPFRC for any change of matrix and fiber properties. The reliability of the proposed model was confirmed from a large experimental investigation performed on smart concrete mixes.

2022 - Finite Torsion of Compressible Circular Cylinders: An Approximate Solution [Articolo su rivista]
Falope, F. O.; Lanzoni, L.; Tarantino, A. M.
abstract

This paper deals with the equilibrium problem of circular cylinders under finite torsion. A three-dimensional kinematic model, where the large twisting of the cylinder is accompanied by transverse contraction and longitudinal extension, is formulated. Following a semi-inverse approach, the displacement field prescribed by the above kinematic model contains as unknowns the longitudinal displacement, the rigid rotation and the transverse stretch of cross sections. To simplify the mathematical formulation, the transverse stretch is assumed to be constant, as it radially undergoes very low variations. This hypothesis produces some approximations in the field equations, but the equilibrium solution obtained is however characterized by a satisfactory accuracy, as shown by the comparisons performed using the numerical techniques of the Finite Element Method (FEM). A Lagrangian analysis is performed and the compressible Mooney-Rivlin law is assumed for the stored energy function. Once evaluated the Piola-Kirchhoff stresses, the unknowns are determined by imposing the equilibrium conditions and the boundary conditions. For the end base of the cylinder two different boundary conditions have been considered, according to which the longitudinal translation of this surface is allowed or prevented. Once the kinematic unknowns have been determined, explicit formulae for displacements, stretches and stresses are provided, which show the role of the geometric and constitutive parameters, as well as of the twisting angle. The results provided by the proposed solution are shown by a series of graphs. The same torsion problem has been addressed with FEM. A very good agreement was found between the results obtained with the two different analyses. Finally, the nonlinear torsion problem was linearized by introducing the hypothesis of smallness of the displacement and deformation fields. With this linearization, the classical solution for the infinitesimal torsion problem was fully retrieved.

2022 - Finite anticlastic bending of hyperelastic laminated beams with a rubberlike core [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

A novel analytical approach to investigate the finite bending of hyperelastic laminated beams is presented. Two different nonlinear material models are taken into account, which are the compressible Mooney-Rivlin for rubberlike mediums and the Saint Venant-Kirchhoff for less deformable materials. The anticlastic bending is included in the formulation and the analytical expression of the transverse radius of curvature is presented. The stress analysis is performed in each layer separately, by considering the actual stored energy function of the constituents, in both Lagrangian and Eulerian frameworks. The finite bending of a sandwich beam is investigated in terms of stresses and stretches.

2022 - Finite bending of non-slender beams and the limitations of the Elastica theory [Articolo su rivista]
Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

The problem of slender solids under finite bending has been addressed recently in Lanzoni and Tarantino (2018). In the present work, such a model is extended to short solids by improving the background formulation. In particular, the model is refined by imposing the vanishing of the axial force over the cross sections. The geometrical neutral loci, corresponding to unstretched and unstressed surfaces, are provided in a closed form. Two approximations of the models are obtained linearising both kinematics and constitutive law and kinematics only. It is shown that the approximations of the model, corresponding to the Euler Elastica formulation, can lead to significant values of the axial stress resultants despite pure bending conditions. For a generic form of compressible energy function, a nonlinear moment–curvature relation accounting for both material and geometric nonlinearities is provided and then specialised for a Mooney–Rivlin material. The obtained results are compared with simulations of 3D finite element models providing negligible errors. The normalisation of the moment–curvature relation provides the dimensionless bending moment as a function of the Eulerian slenderness of the solid. This dimensionless relation is shown to be valid for any aspect ratio of the bent solid and, in turn, it highlights the limitations of the Elastica arising in case of large deformations of solids.

2022 - Finite torsion of compressible hyperelastic cylinders: from simple to restrained torsion [Abstract in Atti di Convegno]
Falope, Federico; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

Abstract

2022 - Multi-phase homogenization procedure for estimating the mechanical properties of shot-earth materials [Articolo su rivista]
Bacciocchi, M.; Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

The paper proposes an analytical homogenization procedure to predict the overall elastic properties of shot-earth, a sustainable composite material made of excavated soil, aggregates and, if needed, a binder for stabilization. A multi-step methodology based on the Mori–Tanaka approach is used to account for the stabilized soil inclusions. This approach is proposed in order to shorten the mix-design procedures and readily provide to the structural engineers a set of mechanical properties of the shot-earth components to be used in the early design phases, when the construction field is not open yet and excavation of the site has not begun. The analytical results were successfully validated through an experimental campaign.

2022 - Predictive models for the ultimate tensile and compressive strengths of HPFRC/UHPFRC [Abstract in Atti di Convegno]
Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

Smart fiber reinforced cementitious composites, like HPFRC and UHPFRC, are today widely ap- plied in the field of the rehabilitation of concrete structures. However, one of the main drawback of HPFRC/UHPFRC is that any modification of the matrix-fibers mix design, due to the market require- ments, affects the mechanical properties of the hardened smart concrete, thus making useless tests performed on previous version of the smart material. For this purpose prediction strength models that link the properties of both fibers and matrix to the performances of the smart concrete are of great practical interest. This work presents a simple and effective model that predicts the compressive and tensile strengths of HPFRC as the fiber properties change. The predictive data obtained by the proposed model were compared to experimental data, showing a good agreement.

2022 - Size effect in single layer graphene sheets and transition from molecular mechanics to continuum theory [Articolo su rivista]
Pelliciari, M.; Pasca, D. P.; Aloisio, A.; Tarantino, A. M.
abstract

The size-dependent mechanical response of graphene is investigated with an entirely nonlinear molecular mechanics approach. Finite element (FE) simulations under uniaxial and equibiaxial tensile loads are carried out on graphene sheets with increasing size. It is found that the response of graphene remains unchanged after a threshold size. Furthermore, anisotropy is observed for large deformations and a negative Poisson's ratio is found after a critical strain for the zigzag uniaxial load case. The threshold size defines the transition to the continuum theory, which is developed as a membrane model in the fully nonlinear context of finite elasticity. The constitutive parameters of the model are calibrated by fitting the results of the FE simulations. The proposed model represents the basis for accurate predictions of the response of graphene subjected to large in-plane deformations. Nonlinear laws for the size-dependent elastic properties of graphene are derived. These laws can be used in linear elasticity-based models to take into account for material nonlinearity, anisotropy and size effect. Finally, a sensitivity analysis of the molecular mechanics model to the parameters of the interatomic potentials is carried out. The discussion of the results gives insights into the influence of each parameter and useful remarks for the molecular mechanics modeling of graphene.

2022 - The formation and growth of a cross kink in a rope under torsion: An interpretation based on structural mechanics [Articolo su rivista]
Lanzoni, L.; Tarantino, A. M.
abstract

The application of large twistings to a thin rope is known to cause the occurrence and evolution of an intermediate cross kink. Using classical linear elastic structural mechanics, the branched equilibrium path, which characterizes the kink formation, has been obtained. This path is characterized by increasing torsional stiffness. Some energy considerations have been formulated to motivate why the rope moves along the branched path generating the cross kink.

2021 - A FE model simulating the damage pattern along the interface of retrofitted cement-based members [Relazione in Atti di Convegno]
Savino, V.; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

2021 - A degrading bouc-wen data-driven model for the cyclic behavior of masonry infilled RC frames [Relazione in Atti di Convegno]
Pelliciari, M.; Sirotti, S.; Di Trapani, F.; Briseghella, B.; Marano, G. C.; Nuti, C.; Tarantino, A. M.
abstract

Mechanics-based macro-models are often used to simulate the cyclic response of infilled reinforced concrete (RC) frames. However, these approaches are affected by uncertainties regarding damage and failure mechanisms. Therefore, this contribution proposes a new smooth data-driven model for the hysteresis of infilled RC frames. The infill panel is modeled through a damage-based Bouc-Wen element, which accounts for both pinching and deterioration of the mechanical characteristics. The parameters of the model are calibrated from an experimental data set of cyclic responses of RC infilled frames. Analytical correlations between parameters and geometric and mechanical characteristics of the infilled frame are derived. Blind validation tests are carried out in order to demonstrate the effectiveness of the proposed model.

2021 - A nonlinear molecular mechanics model for graphene subjected to large in-plane deformations [Articolo su rivista]
Pelliciari, M.; Tarantino, A. M.
abstract

In this paper we present a fully nonlinear stick-and-spring model for graphene subjected to in-plane deformations. The constitutive behaviors of sticks and springs are defined, respectively, by the modified Morse potential and a nonlinear bond angle potential. The equilibrium equations of the representative cell are written considering large displacements of the nodes (atoms) and the stability of the solutions is assessed using an energy criterion. The solutions for the uniaxial load cases along armchair and zigzag directions show that graphene is isotropic for small deformations, while it exhibits anisotropy when subjected to large deformations. Moreover, graphene shows a negative Poisson's ratio after a critical value of deformation. In the case of equibiaxial load, multiple solutions of the equilibrium are found and graphene can experience asymmetric deformations despite the symmetry of the external loads. The nonlinear formulation of the equilibrium is then linearized by introducing the hypothesis of small displacements. The expressions of Young's modulus and Poisson's ratio are derived.

2021 - Analytical solutions for vibrations and buckling analysis of laminated composite nanoplates based on third-order theory and strain gradient approach [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

A nonlocal model based on the strain gradient approach is developed within the framework of the Third-order Shear Deformation Theory (TSDT) for the investigation of the free vibrations and the critical buckling loads of laminated composite nanoplates. The theory is suitable to deal with thick and thin plates since it includes also the First-order Shear Deformation Theory (FSDT) and the Classical Laminated Plate Theory (CLPT). An analytical procedure based on the Navier approach is employed to obtain the solutions, which are discussed highlighting the effects of the strain gradient, as well as the influence of the geometric ratios and mechanical properties, on the results. The paper aims at providing reliable benchmarks for further developments of the topic to be used as references in future comparison tests.

2021 - Bending of hyperelastic beams made of transversely isotropic material in finite elasticity [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

The paper aims to investigate the finite bending of hyperelastic beams composed of transversely isotropic soft materials. The constitutive laws are obtained by including the transverse isotropy effects in the compressible Mooney-Rivlin model. A suitable expression for the stored energy function is introduced for this purpose, showing its dependency on five material invariants. A fully nonlinear three-dimensional beam model, including the anticlastic effect, is developed. The general analytical formulation allows to consider the influence of transverse isotropy on the Piola-Kirchhoff and Cauchy stress components, since it is presented in both Lagrangian and Eulerian frameworks. The validity of the current model is finally discussed. This study is justified by many innovative applications which require the use of transversely isotropic components, such as the finite bending of soft robots or biological systems.

2021 - Bending of nanobeams in finite elasticity [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

Motivated by the need to have a fully nonlinear beam model usable at the nanoscale, in this paper, the equilibrium problem of inflexed nanobeams in the context of nonlocal finite elasticity is investigated. Considering both deformations and displacements large, a three-dimensional kinematic model has been proposed. Extending the linear nonlocal Eringen theory, a constitutive law in integral form for the nonlocal Cauchy stress tensor has been defined. Finally, by imposing the equilibrium conditions, the governing equations are obtained. These take the form of a coupled system of three equations in integral form, which is solved numerically. Explicit formulae for displacements, stretches and stresses in every point of the nanobeam are derived. By way of example, a simply supported nanobeam, which is inflexed under nonlinear conditions, has been considered. The nonlocal effects on the deformation and internal actions are shown through some graphs and discussed in detail.

2021 - Development and Validation of New Bouc-Wen Data-Driven Hysteresis Model for Masonry Infilled RC Frames [Articolo su rivista]
Sirotti, S.; Pelliciari, M.; Di Trapani, F.; Briseghella, B.; Carlo Marano, G.; Nuti, C.; Tarantino, A. M.
abstract

During the last years, several mechanics-based macromodels have been proposed to assess the cyclic response of infilled RC frames. However, the uncertainties behind the assumptions on damage and failure mechanisms compromise the reliability of such approaches. For this reason, this paper proposes a new data-driven hysteresis model for the cyclic response of infilled RC frames. The infill panel is schematized as a single-degree-of-freedom element, whose constitutive law is given by the proposed hysteresis model. The model combines a degrading Bouc-Wen element with a slip-lock element, which is introduced specifically to reproduce the pinching effect due to crack openings in the masonry panel. The parameters governing the model have clear physical meanings and are calibrated on the basis of an experimental data set of cyclic responses of single-story single-bay RC infilled frames. The calibrations are carried out by means of a genetic algorithm-based optimization. Analytical correlation laws linking the model parameters with geometric and mechanical properties of the RC infilled frame are proposed and validated by blind validation tests. Results show adequate accuracy of the model in reproducing the cyclic response of infilled frames characterized by significantly different geometrical and mechanical features. The model is defined by a smooth analytical hysteresis law, with great advantages regarding numerical stability and computational effort. This makes it suitable for dynamic and stochastic simulations.

2021 - Dispositivo per l'isolamento di apparecchiature industriali, strutture e infrastrutture civili basato su moduli reticolari a traliccio [Brevetto]
Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Pelliciari, Matteo; Tarantino, Angelo Marcello; Salardi, Enrico
abstract

2021 - Equilibrium and Stability of Anisotropic Hyperelastic Graphene Membranes [Articolo su rivista]
Pelliciari, M.; Tarantino, A. M.
abstract

The lack of experimental investigations on graphene fostered researchers to focus on its mechanical modeling. Being graphene a one-atom-thick sheet, many authors developed continuum membrane models to analyze its mechanical behavior. However, an entirely nonlinear approach in finite elasticity has not been presented so far. In this work, the equilibrium problem of anisotropic hyperelastic graphene membranes is addressed. Strain and stress measures are expressed under the hypothesis of homogeneous deformations and the boundary-value problem is formulated for a graphene membrane subjected to biaxial loads. The stability of the equilibrium configurations is assessed through an energy criterion. Explicit relations between stretches and stresses of the membrane are derived for the cases of uniaxial and equibiaxial loads. Unexpectedly, bifurcation and multiple equilibrium solutions are found when graphene is subjected to equibiaxial loads. A linearization of the finite theory is presented and the expressions of Young’s modulus and Poisson’s ratio of graphene are derived. The formulation proposed in this work may be the basis for accurate investigations of the mechanics of graphene subjected to large deformations.

2021 - Finite bending of hyperelastic beams with transverse isotropy generated by longitudinal porosity [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

The paper deals with the finite bending analysis of transversely isotropic hyperelastic slender beams made of a neo-Hookean material with longitudinal voids. The fully nonlinear behavior of the structures is presented in the framework of three-dimensional finite elasticity. A semi-inverse approach is used to describe the beam kinematics, which includes the anticlastic effect. The theoretical framework is developed in both Lagrangian and Eulerian reference systems. Explicit formulas are obtained for stretches and stresses, in a general framework valid for transversely isotropic beams. The effect of porosity on the Piola-Kirchhoff and Cauchy stress components is then discussed. The results are all obtained and validated analytically, and could be helpful to model structural systems in the fields of bioengineering and soft-robotics which exhibit both large displacements and deformations.

2021 - Large nonuniform bending of beams with compressible stored energy functions of polynomial-type [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

The large bending of beams made with complex materials finds application in many emerging fields. To describe the nonlinear behavior of these complex materials such as rubbers, polymers and biological tissues, stored energy functions of polynomial-type are commonly used. Using polyconvex and compressible stored energy functions of polynomial-type, in the present paper the equilibrium problem of slender beams in the fully nonlinear context of finite elasticity is formulated. In the analysis, the bending is considered nonuniform, the complete three-dimensional kinematics of the beam is taken into account and both deformation and displacement fields are deemed large. The governing equations take the form of a coupled system of three equations in integral form, which is solved numerically through an iterative procedure. Explicit formulae for displacements, stretches and stresses in every point of the beam, following both Lagrangian and Eulerian descriptions, are derived. By way of example, a complete analysis has been performed for the Euler beam.

2021 - Linear eigenvalue analysis of laminated thin plates including the strain gradient effect by means of conforming and nonconforming rectangular finite elements [Articolo su rivista]
Bacciocchi, M.; Fantuzzi, N.; Luciano, R.; Tarantino, A. M.
abstract

The paper presents a finite element method to investigate the critical buckling loads and the natural frequencies of laminated Kirchhoff plates including the nonlocal strain gradient effect, which could have considerably consequences at the nanoscale. With respect to the existing literature, the proposed numerical methodology is developed to deal with general stacking sequences of orthotropic layers with arbitrary orientations and various boundary conditions. The resulting membrane-bending coupling is emphasized in the formulation, which requires to study the whole set of partial differential equations. The membrane and bending degrees of freedom are all approximated by means of Hermite interpolating functions with higher-order continuity requirements. To this aim, regular rectangular finite elements based on conforming (C) and nonconforming (NC) approaches are used. A wide validation procedure is carried out to prove the effectiveness of the proposed formulation. A set of new results is presented for general mechanical configurations with arbitrary restraints.

2021 - Nonuniform bending theory of hyperelastic beams in finite elasticity [Articolo su rivista]
Lanzoni, L.; Tarantino, M.
abstract

This paper deals with the equilibrium problem of slender beams inflexed under variable curvature in the framework of fully nonlinear elasticity. For the specific case of uniform flexion, the authors have recently proposed a mathematical model. In that analysis, the complete three-dimensional kinematics of the beam is taken into account and both deformations and displacements are considered large. In the present paper, the kinematics of the aforementioned model has been reformulated taking into account beams under variable curvature. Subsequently, focusing on the local determination of the curvature, new equilibrium conditions on cross sections are introduced in the mathematical formulation. The governing equations take the form of a coupled system of three equations in integral form, which is solved numerically through an iterative procedure. Therefore, for the generic class of hyperelastic and isotropic materials, explicit formulae for the displacement field, the stretches and stresses in every point of the beam, following both Lagrangian and Eulerian descriptions, are derived. The analysis allows studying a very wide class of equilibrium problems for nonlinear beams under different restraint conditions and subject to generic external load systems. By way of example, the Euler beam has been considered and the formulae obtained have been specialized for a specific neoprene rubber material, the constitutive constants of which have been determined experimentally. The shapes assumed by the beam as the load multiplier increases are shown through some graphs. The distributions of stretches and Cauchy stresses are plotted for the most stressed cross section. Some comparisons are made using a FE code. In addition, the accuracy of the obtained solution is estimated by evaluating a posteriori that the equilibrium equations are locally satisfied.

2021 - On the anticlastic bending of solids at finite strains [Abstract in Atti di Convegno]
Falope, Fo; Lanzoni, L; Tarantino, Am
abstract

The present work deals with the problem of compressible isotropic hyperelastic solids under finite bending. The problem is fully nonlinear and, conversely to the classical Rivlin solution [1], it is formulated in the framework of three-dimensional kinematics involving both large displacements and strains according to the context of finite elasticity. The model entails three kinematic assumptions, which stand for the planarity of the cross sections (Bernoulli-Navier hypothesis), the invariance of the curvature along the longitudinal direction of the solid (uniform bending) and the curvature of the cross sections (anticlastic curvature), that is assumed constant along the width of the solid [2]. Based on the semi-inverse approach and according to the kinematic assumptions, the 3D displacement field is found, and, in turn, the deformation gradient is assessed. Then, the equilibrium conditions, specialized for a compressible Mooney-Rivlin material, provide proper relations among the unknown kinematic parameters, thus leading to the closure of the problem. Emphasis in placed on the “moment-curvature relation”, which is found to be governed by two independent dimensionless parameters: the Eulerian slenderness and the compactness index of the solid cross sections [3]. Similarity is observed with respect the previous works of Lamb (1890) regarding the mechanical response of bent plates and the experiments performed by Searle (1933) as well. Moreover, such an analysis allows broadening the “Elastica” to the more general context of finite elasticity. In this work, the main results provided by the theoretical model are compared with those obtained by FE simulations and an experimental investigation based on a specifically designed mechanical apparatus, founding good agreement also for the case of extremely inflexed solids.

2021 - Snap-through and Eulerian buckling of the bi-stable von Mises truss in nonlinear elasticity: A theoretical, numerical and experimental investigation [Articolo su rivista]
Falope, F. O.; Pelliciari, M.; Lanzoni, L.; Tarantino, A. M.
abstract

In this paper, the equilibrium and stability of the von Mises truss subjected to a vertical load is analyzed from theoretical, numerical and experimental points of view. The bars of the truss are composed of a rubber material, so that large deformations can be observed. The analytical model of the truss is developed in the fully nonlinear context of finite elasticity and the constitutive behavior of the rubber is modeled using a Mooney–Rivlin law. The constitutive parameters are identified by means of a genetic algorithm that fits experimental data from uniaxial tests on rubber specimens. The numerical analysis is performed through a finite element (FE) model. Differently from the analytical and FE simulations that can be found in the literature, the models presented in this work are entirely developed in three-dimensional finite elasticity. Experiments are conducted with a device that allows the rubber specimens to undergo large axial deformations. For the first time, snap-through is observed experimentally on rubber materials, showing good agreement with both theoretical and numerical results. Further insights on Eulerian buckling of the rubber specimens and its interaction with the snap-through are given. A simple formulation to determine the critical load of the truss is presented and its accuracy is validated through experimental observation. Comparisons with a linear elasticity based approach demonstrate that an accurate prediction of snap-through and Eulerian buckling requires nonlinear formulations, such as the ones proposed in this work.

2021 - Snap-through and Eulerian buckling of the von Mises truss [Relazione in Atti di Convegno]
Pelliciari, Matteo; Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

2021 - Snap-through of a bi-stable truss in finite elasticity [Relazione in Atti di Convegno]
Pelliciari, M.; Falope, F. O.; Lanzoni, L.; Tarantino, A. M.
abstract

2021 - Special issue: “advances in structural mechanics modeled with fem” [Articolo su rivista]
Tarantino, A. M.; Majorana, C.; Luciano, R.; Bacciocchi, M.
abstract

The current Special Issue entitled "Advances in Structural Mechanics Modeled with FEM" aims to collect several numerical investigations and analyses focused on the use of the Finite Element Method (FEM) [...].

2021 - Third-order theory for the bending analysis of laminated thin and thick plates including the strain gradient effect [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

The aim of the paper is the development of a third-order theory for laminated composite plates that is able to accurately investigate their bending behavior in terms of displacements and stresses. The starting point is given by the corresponding Reddy’s Third-order Shear Deformation Theory (TSDT). This model is then generalized to consider simultaneously the Classical Laminated Plate Theory (CLPT), as well as the First-order Shear Deformation Theory (FSDT). The constitutive laws are modified according to the principles of the nonlocal strain gradient approach. The fundamental equations are solved analytically by means of the Navier methodology taking into account cross-ply and angle-ply lamination schemes. The numerical applications are presented to highlight the nonlocal effects on static behavior.

2020 - A cohesive FE model for simulating the cracking/debonding pattern of composite NSC-HPFRC/UHPFRC members [Articolo su rivista]
Savino, Vincenzo; Lanzoni, Luca; Tarantino, Angelo Marcello; Viviani, Marco
abstract

The aim of this work is to propose to practitioners a simple cohesive Finite-Element model able to simulate the cracking/debonding pattern of retrofitted concrete elements, in particular Normal-Strength-Concrete members (slabs, bridge decks, pavements) rehabilitated by applying a layer of High-Performance or Ultra-High-Performance Fiber-Reinforced-Concrete as overlay. The interface was modeled with a proper nonlinear cohesive law which couples mode I (tension-crack) with mode II (shear-slip) behaviors. The input parameters of the FE simulation were provided by a new bond test which reproduces a realistic condition of cracking/debonding pattern. The FE simulations were accomplished by varying the overlay materials and the moisture levels of the substrate surface prior to overlay, since findings about their influence on the bond performances are still controversial. The proposed FE model proved to effectively predict the bond failure of composite NSC-HPFRC/UHPFRC members.

2020 - A cohesive model to predict the loading bond capacity of concrete structures repaired/reinforced with HPFRC/UHPFRC and stressed to mixed mode [Articolo su rivista]
Savino, Vincenzo; Lanzoni, Luca; Tarantino, Marcello; Viviani, Marco
abstract

The risk of cracking/debonding of a cement overlay used to repair or strengthen an existing structure is still a key issue. Current bond test methods are not designed to measure the combined effect of peeling (mode I) and shear (mode.II) on the interface. A few existing models propose theoretical approaches to predict that, but they were fitted on specific cases and lack in generality. In addition, controversial opinions about the influence of both the moisture level of the substrate surface prior to the application of the overlay and properties of the latter on the loading bond capacity call for further investigations. In this work, a cohesive model is developed to predict the loading bond capacity of an existing concrete structure overlaid by a layer of HPFRC/UHPFRC. Different bond tests were specifically designed for calibrating the cohesive pa-rameters employed into the model, which also takes into account the type of the overlay used and the moisture conditioning level. An experimental cam-paign confirmed the reliability of the predictions of the proposed theoretical model.

2020 - A degrading Bouc–Wen model for the hysteresis of reinforced concrete structural elements [Articolo su rivista]
Pelliciari, Matteo; Briseghella, Bruno; Tondolo, Francesco; Veneziano, Luigi; Nuti, Camillo; Greco, Rita; Lavorato, Davide; Tarantino, A. M.
abstract

This paper presents a smooth hysteresis model for reinforced concrete (RC) structural elements based on the differential equation of the Bouc?Wen model. Stiffness degradation and strength degradation are defined by introducing a damage index that includes both dissipated energy and maximum displacement. The pinching effect acts directly on the stiffness of the system and is controlled by an activation energy. The degrading functions are connected to the actual processes with which the damage occurs, thereby giving each parameter a physical meaning. The simple formulation of the model allows a straightforward identification of the best-fitting parameters and an easy interpretation of the results. Applications to the cyclic behaviour of RC structural elements demonstrate that the model is well capable of describing complex hysteretic behaviours involving degradation and pinching effects.

2020 - Critical buckling load of honeycomb sandwich panels reinforced by three-phase orthotropic skins enhanced by Carbon nanotubes [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

2020 - Dispositivo smorzatore assiale ad elastomeri [Brevetto]
Falope, FEDERICO OYEDEJI; Pelliciari, Matteo; Lanzoni, Luca; Tarantino, Angelo Marcello; Salardi, Enrico
abstract

2020 - Equilibrium Paths for von Mises Trusses in Finite Elasticity [Articolo su rivista]
Pelliciari, M.; Tarantino, A. M.
abstract

This paper deals with the equilibrium problem of von Mises trusses in nonlinear elasticity. A general loading condition is considered and the rods are regarded as hyperelastic bodies composed of a homogeneous isotropic material. Under the hypothesis of homogeneous deformations, the finite displacement fields and deformation gradients are derived. Consequently, the Piola-Kirchhoff and Cauchy stress tensors are computed by formulating the boundary-value problem. The equilibrium in the deformed configuration is then written and the stability of the equilibrium paths is assessed through the energy criterion. An application assuming a compressible Mooney-Rivlin material is performed. The equilibrium solutions for the case of vertical load present primary and secondary branches. Although, the stability analysis reveals that the only form of instability is the snap-through phenomenon. Finally, the finite theory is linearized by introducing the hypotheses of small displacement and strain fields. By doing so, the classical solution of the two-bar truss in linear elasticity is recovered.

2020 - Equilibrium of the von mises truss in nonlinear elasticity [Abstract in Atti di Convegno]
Pelliciari, M.; Tarantino, A. M.
abstract

In this contribution, a nonlinear formulation of the equilibrium problem of the von Mises truss (or two-bar truss) is presented. The bars are regarded as three-dimensional bodies composed of a homogeneous and isotropic material. The displacement fields are written under the assumption of homogeneous deformations and, consequently, the boundary-value problem is formulated. The relations governing the equilibrium of each body are thus derived and the global equilibrium of the von Mises truss under a general loading condition is written. The stability of the equilibrium solutions is assessed through the energy criterion. An application considering a compressible Mooney-Rivlin material shows interesting post-critical behaviors, involving snap-through and multiple branches.

2020 - Equilibrium paths of a three-bar truss in finite elasticity with an application to graphene [Articolo su rivista]
Pelliciari, M.; Tarantino, A. M.
abstract

This paper presents the formulation of the equilibrium problem of a three-bar truss in the nonlinear context of finite elasticity. The bars are composed of a homogeneous, isotropic, and compressible hyperelastic material. The equilibrium equations in the deformed configuration are derived under the assumption of homogeneous deformations and the stability of the solutions is assessed through the energy criterion. The general formulation is then specialized for a compressible Mooney–Rivlin material. The results for both vertical and horizontal load cases show unexpected post-critical behaviors involving several branches, stable asymmetrical configurations, bifurcation, and snap-through. The three-bar truss studied here is not only a benchmark test for the numerical analysis of nonlinear truss structures, but also a representative system for the unit cell of the graphene hexagonal lattice. Therefore, an application to graphene is performed by simulating the covalent bonds between carbon atoms as the bars of the truss, characterized by the modified Morse potential. The results provide insights on the internal mechanisms that take place when graphene undergoes large in-plane deformations, whose influence should be considered when developing molecular mechanics and continuum models in nonlinear elasticity.

2020 - FE Analyses of Hyperelastic Solids under Large Bending: The Role of the Searle Parameter and Eulerian Slenderness [Articolo su rivista]
Falope, Federico; Lanzoni, Luca; Tarantino, Marcello
abstract

A theoretical model concerning the finite bending of a prismatic hyperelastic solid has been recently proposed. Such a model provides the 3D kinematics and the stress field, taking into account the anticlastic effects arising in the transverse cross sections also. That model has been used later to extend the Elastica in the framework of finite elasticity. In the present work, Finite Element (FE) analyses of some basic structural systems subjected to finite bending have been carried out and the results have been compared with those provided by the theoretical model performed previously. In the theoretical formulation, the governing equation is the nonlinear local relationship between the bending moment and the curvature of the longitudinal axis of the bent beam. Such a relation has been provided in dimensionless form as a function of the Mooney–Rivlin constitutive constants and two kinematic dimensionless parameters termed Eulerian slenderness and compactness index of the cross section. Such parameters take relevance as they are involved in the well-known Searle parameter for bent solids. Two significant study cases have been investigated in detail. The results point out that the theoretical model leads to reliable results provided that the Eulerian slenderness and the compactness index of the cross sections do not exceed fixed threshold values.

2020 - Mechanics of high-flexible beams under live loads [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello; Angelo, Marcello
abstract

In this paper the mathematical formulation of the equilibrium problem of high-flexible beams in the framework of fully nonlinear structural mechanics is presented. The analysis is based on the recent model proposed by L. Lanzoni and A.M. Tarantino: The bending of beams in finite elasticity in J. Elasticity (2019) doi:10.1007/s10659-019-09746-8 2019. In this model the complete three-dimensional kinematics of the beam is taken into account, both deformations and displacements are considered large and a nonlinear constitutive law in assumed. After having illustrated and discussed the peculiar mechanical aspects of this special class of structures, the criteria and methods of analysis have been addressed. A classification of the structures based on the degree of kinematic constraints has been proposed, distinguishing between isogeometric and hypergeometric structures. External static loads dependent on deformation (live loads) are also considered. The governing equations are derived on the basis of a moment-curvature relationship obtained in L. Lanzoni and A.M. Tarantino: The bending of beams in finite elasticity in J. Elasticity (2019) doi:10.1007/s10659-019-09746-8 2019. The governing equations take the form of a highly nonlinear coupled system of equations in integral form, which is solved through an iterative numerical procedure. Finally, the proposed analysis is applied to some popular structural systems subjected to dead and live loads. The results are compared and discussed.

2020 - Modeling and numerical investigation of the viscoelastic behavior of laminated concrete beams strengthened by CFRP strips and Carbon nanotubes. [Abstract in Rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

2020 - Shot-earth for sustainable constructions [Articolo su rivista]
Curto, Andrea; Lanzoni, L; Tarantino, Am; Viviani, Marco
abstract

Earth has been used worldwide as a building material for centuries and it is still one of the most used construction materials. In many countries the excavated soil is becoming one of the largest construction waste and its disposal is costly and problematic. For this reason, there is a rising interest in employing the excavated soil directly in field, possibly as an added value construction material. In this paper a new type of rammed earth is presented. This new material is based on the shotcrete technology and has been named shot-earth. A mix of stabilized soil, aggregates and water is consolidated by high speed projection rather than by mechanical compaction to obtain both structural and non-structural elements. The first characterization of the physical properties of this material has shown the great potential of this technology

2020 - The Bending of Beams in Finite Elasticity [Articolo su rivista]
Lanzoni, L.; Tarantino, A. M.
abstract

In this paper the analysis for the anticlastic bending under constant curvature of nonlinear solids and beams, presented by Lanzoni, Tarantino (J. Elast. 131:137–170,2018), is extended and further developed for the class of slender beams. Following a semi-inverse approach, the problem is studied by a three-dimensional kinematic model for the longitudinal inflexion, which is based on the hypothesis that cross sections deform preserving their planarity. A compressible Mooney-Rivlin law is assumed for the stored energy function and from the equilibrium equations, the free parameter of the kinematic model is computed. Thus, taking into account the three-dimensionality of the beam, explicit formulae for the displacement field, the stretches and stresses in every point of the body, following both Lagrangian and Eulerian description, are derived. Subsequently, slender beams under variable curvature were examined, focusing on the local determination of the curvature and bending moment along the deformed beam axis. The governing equations take the form of a coupled system of three equations in integral form, which is solved numerically. The proposed analysis allows to study a very wide class of equilibrium problems for nonlinear beams under different restraint conditions and subject to generic external load systems. By way of example, the Euler beam and a cantilever beam loaded by a dead or live (follower) concentrated force applied at the free end have been considered, showing the shape assumed by the beam as the load multiplier increases.

2019 - An extended model to predict the compressive, tensile and flexural strengths of HPFRCs and UHPFRCs: Definition and experimental validation [Articolo su rivista]
Savino, Vincenzo; Lanzoni, Luca; Tarantino, Angelo Marcello; Viviani, Marco
abstract

High manufacturing costs of UHPFRC and expensive and time-consuming tests performed to understand the mechanical response under loading restrict still its wider applications in thefield of the structural engineering. Predictive models can be useful to reduce the number of requested tests and to optimize the amount of compounds of the mixture, for example detecting the minimal dosage offibers necessary to attain a given tensile strength and toughness as well. Currently, not many predictive models do exist and one of the most recent, developed in order to estimate the compressive and tensile responses of HPFRCs, was not notably suitable for UHPFRCs. The main purpose of this work concerns the extension of such a model, in order to predict the mechanical response (inflexion as well) of a given HPFRC/UHPFRC for any change of matrix and fiber properties. Theoretical results were compared with experimental data, thus conforming some shortcomings of the previous model. Once the matrix andfiber properties of a marked UHPFRC were selected, the extended model was used to predict the tensile andflexural bending responses of a full scale UHPFRC structural beam, showing good agreement with the experimental results.

2019 - Bending device and anticlastic surface measurement of solids under large deformations and displacements [Articolo su rivista]
Falope, F. O.; Lanzoni, L.; Tarantino, A. M.
abstract

Large bending of elastic bodies gives rise to significant transverse effects. Based on a recent theoretical model in the context of finite elasticity, both the longitudinal and anticlastic curvatures in bent solids under large deformation and displacement can be accurately assessed. In order to experimentally investigate the anticlastic deformation induced by large inflexion and corroborate the theoretical predictions, a properly designed mechanical bending device is here proposed. By imposing a rotation at the ends of the sample, both the longitudinal and anticlastic curvatures are measured by DIC (digital image correlation) monitoring instrumentation and compared with the theoretical results, finding good agreement. Compact analytical formulae for assessing the radii of curvature within the thickness of the sample are provided. Conversely to existing studies of the anticlastic surface induced by infinitesimal bending, the present analysis takes into account large through-to-thickness curvature variations, whose knowledg can plays a key role for a wide class of mechanical applications.

2019 - Bending of beams in finite elasticity and some applications [Abstract in Atti di Convegno]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

The 2D Rivlin solution concerning the finite bending of a prismatic solid has been recently extended by accounting for the complete 3D displacement field [1]. In particular, the relationship between the principal and transverse (anticlastic) deformation of a bent solid has been investigated, founding the coupling relationships among three kinematic parameters which govern the problem. Later, based on the formulation reported in [1], and making reference to a (hyper)elastic material, the formulation has been extended to slender beams by introducing some simplifying assumptions [2]. This leads to a challenging relation between the external bending moment m and the curvature R01 of the longitudinal axis, which involves both the constitutive and geometric parameters of the beam. This relation can be viewed as a generalization of the Elastica [3]. However, such a relationship can be simplified through a series expansion, thus obtaining a reliable moment-curvature relation as follows [4], being a, b, c the constitutive parameters involved in the stored energy function according to a compressible Mooney-Rivlin material, whereas r denotes the anticlastic radius of the cross section [1]. In eqn (1)1 the radius of curvature R0 depends on the curvilinear abscissa s describing the beam axis in its deformed configuration. The rotation  of the beam cross section follows from the derivative of the curvature with respect abscissa s, i.e. ’(s) = R01(s). Thus, the axial and vertical components of the displacement field and the rotation of the beam cross section are found to be coupled in a set of three equations in integral form, which is handled in an iterative procedure in order to analyse elastic structures exhibiting deformations and displacements both large. Some basic structural schemes under both dead and live loads are here investigated, thus assessing the deformed configuration and the arising internal forces into the beam. It is found that the magnitude of the external loads strongly affects the qualitative distribution of the axial and shear forces and the bending moment in the inflexed beam, giving rise to a solution which completely differs to that corresponding to infinitesimal strains and small displacements.

2019 - Finite bending of beams with anticlastic effect: analytical model, experimental test and FE modeling [Abstract in Atti di Convegno]
Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

A recent model of a bent solid in finite elasticity appears in Literature [1]. Making reference to a compressible Mooney-Rivlin material, such a model is able to describe properly the anticlastic effect arising in a bent beam made of a rubber-like material. An experimental device is here presented (see Figure 1) aimed at simulating pure bending. In particular, the device lets the specimen free to exhibit its own elastic retaining force. Accordingly, the bent sample assumes the shape of an arc of circumference. With the aid of a DIC optical monitoring system, the experimental displacement field is acquired during the deformation process varying the angles imposed at the final beam cross sections. For different rubber specimens, based on a theoretical model [2], both compression and tensile tests have been performed in order to properly characterize the constitutive parameters. Once the constitutive parameters have been found, by means of non-linear fitting experimental data, a FE model has been carried out in order to reproduce the experimental test. A good agreement is found among analytical, experimental and numerical results, thus showing the reliability of the proposed experimental device together with the consistency of the basic hypotheses of the theoretical model.

2019 - Free vibrations of sandwich plates with damaged soft-core and non-uniform mechanical properties: Modeling and Finite Element analysis. [Articolo su rivista]
Bacciocchi, M.; Luciano, R.; Majorana, C.; Tarantino, A. M.
abstract

2019 - Modèle prédictif visant à optimiser les composants du BFUP en réponseaux exigences d’application [Abstract in Atti di Convegno]
Savino, Vincenzo; Lanzoni, Luca; Tarantino, Angelo Marcello; Viviani, Marco
abstract

Tous les matériaux de construction doivent être caractérisés préalablement, pour qu’ils répondent aux exigences demandées par les concepteurs. Pour le Béton Fibré Ultra Performant (BFUP), l’innovation continue de ses composants, due aux progrès technologiques, en modifie les propriétés mécaniques en comparaison à la version précédente du même produit. Cela demande de nouveaux essais de formulation du mélange visant à atteindre les performances rigoureuses demandées par les concepteurs. En outre, le coût élevé de production, principalement imputable à la présence des fibres métalliques dans le mélange, limite une exploitation plus étendue d’un tel produit sur le marché. Dans cet article, un modèle prédictif de résistance a été développé pour détecter le type et la quantité minimale de fibres à ajouter dans une matrice cimentaire donnée, afin de satisfaire les exigences de performances demandées et de réduire le nombre de matériaux différents à tester, en guidant le choix d’optimisation de la composition du mélange. Le modèle, validé par une étude expérimentale, a enfinété appliqué dans un cas pratique.

2019 - Natural frequency Analysis of Functionally Graded Orthotropic Cross-Ply Plates Based on the Finite Element Method [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

2019 - The Bending Theory of Fully Nonlinear Beams [Monografia/Trattato scientifico]
Tarantino, A. M.; Lanzoni, L.; Falope, F. O.
abstract

This book presents the bending theory of hyperelastic beams in the context of finite elasticity. The main difficulties in addressing this issue are due to its fully nonlinear framework, which makes no assumptions regarding the size of the deformation and displacement fields. Despite the complexity of its mathematical formulation, the inflexion problem of nonlinear beams is frequently used in practice, and has numerous applications in the industrial, mechanical and civil sectors. Adopting a semi-inverse approach, the book formulates a three-dimensional kinematic model in which the longitudinal bending is accompanied by the transversal deformation of cross-sections. The results provided by the theoretical model are subsequently compared with those of numerical and experimental analyses. The numerical analysis is based on the finite element method (FEM), whereas a test equipment prototype was designed and fabricated for the experimental analysis. The experimental data was acquired using digital image correlation (DIC) instrumentation. These two further analyses serve to confirm the hypotheses underlying the theoretical model. In the book’s closing section, the analysis is generalized to the case of variable bending moment. The governing equations then take the form of a coupled system of three equations in integral form, which can be applied to a very wide class of equilibrium problems for nonlinear beams.

2019 - The bending of fully nonlinear beams. Theoretical, numerical and experimental analyses [Articolo su rivista]
Falope, Federico; Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with the equilibrium problem of fully nonlinear beams in bending by extending the model for the anticlastic flexion of solids recently proposed by Lanzoni and Tarantino (2018) in the context of finite elasticity. In the first part of the paper it is shown, through a parametric analysis, that some geometrical parameters of the displacement field lose importance when slender beams are considered. Therefore, kinematics is reformulated and, subsequently, a fully nonlinear theory for the bending of slender beams is developed. In detail, no hypothesis of smallness is introduced for the deformation and displacement fields, the constitutive law is considered nonlinear and the equilibrium is imposed in the deformed configuration. Explicit formulas are obtained which describe the displacement fields of the inflexed beam, the stretches and the stresses for each point of the beam using both the Lagrangian and Eulerian descriptions. All these formulas are linearized by retrieving the classical formulae of the infinitesimal bending theory of beams. In the second part of the paper the theoretical results are compared with those provided by numerical and experimental analyses developed for the same equilibrium problem with the aim of justify the hypotheses underlying the theoretical model. The numerical model is based on the finite element (FE) method, whereas a test equipment prototype is designed and manufactured for the experimental analysis.

2019 - Time-dependent behavior of viscoelastic three-phase composite plates reinforced by Carbon nanotubes [Articolo su rivista]
Bacciocchi, M.; Tarantino, A. M.
abstract

2018 - Double lap shear test on steel fabric reinforced cementitious matrix (SFRCM) [Articolo su rivista]
Falope, F. O.; Lanzoni, L.; Tarantino, Angelo Marcello
abstract

The present work deals with the experimental characterization of the mechanical behaviour of a galvanized steel fabric reinforced cementitious matrix (SFRCM).

2018 - Finite Anticlastic Bending of Hyperelastic Solids and Beams [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with the equilibrium problem in nonlinear elasticity of hyperelastic solids under anticlastic bending. A three-dimensional kinematic model, where the longitudinal bending is accompanied by the transversal deformation of cross sections, is formulated. Following a semi-inverse approach, the displacement field prescribed by the above kinematic model contains three unknown parameters. A Lagrangian analysis is performed and the compressible Mooney-Rivlin law is assumed for the stored energy function. Once evaluated the Piola-Kirchhoff stresses, the free parameters of the kinematic model are determined by using the equilibrium equations and the boundary conditions. An Eulerian analysis is then accomplished to evaluating stretches and stresses in the deformed configuration. Cauchy stress distributions are investigated and it is shown how, for wide ranges of constitutive parameters, the obtained solution is quite accurate. The whole formulation proposed for the finite anticlastic bending of hyperelastic solids is linearized by introducing the hypothesis of smallness of the displacement and strain fields. With this linearization procedure, the classical solution for the infinitesimal bending of beams is fully recovered

2018 - Longitudinal Joint Performance of a Concrete Hollow Core Slab Bridge [Articolo su rivista]
Barbieri, D. M.; Chen, Y.; Mazzarolo, E.; Briseghella, B.; Tarantino, A. M.
abstract

Hollow core slab bridges are constructed by placing prefabricated or prestressed box beams adjacent to each other, grouting the small longitudinal space (hinge-joint) between the slabs and casting a reinforced concrete deck. The longitudinal cracking appearing at hinge-joint locations leads to a premature deterioration of the deck. This paper presents a theoretical and experimental study of a hollow core slab bridge composed of three beams and a cast-in-place deck. A real-size specimen was built according to Chinese code specifications. The behavior of the longitudinal joints was investigated by applying the standard vehicle load. The tests do not highlight any longitudinal cracks. A finite element model was created from the experimental data. A finite element parametric analysis revealed some practical design indications regarding the following inputs: deck thickness, concrete strength, and hinge-joint steel bars. Furthermore, these analyses testify that C-shape and X-shape stirrups do not play an active role in preventing the joint longitudinal cracks. This research confirms the reliability of the design method, at least for static loads, while further studies are needed to investigate the effect of both periodical loadings and different temperatures on upper and lower surfaces of the beams.

2018 - Modified hinged beam test on steel fabric reinforced cementitious matrix (SFRCM) [Articolo su rivista]
Falope, F. O.; Lanzoni, L.; Tarantino, A. M.
abstract

An experimental campaign based on modied hinged beam test (MhBT) set-up has been reported in the present study. The samples consist of two concrete blocks coupled by a proper hinge device and laminated with steel wire fabrics embedded in a cementitious mortar layer. Two kinds of fabrics, made of galvanized steel strands with dierent mesh spacing, have been used to reinforce the concrete joists. With the aid of a DIC monitoring system, slippage prole at the interface between the concrete support and the mortar laminate along the contact region has been assessed, together with the fracture opening. Force vs slippage at the interface has been retrieved for the sampled tested according to the MhBT set-up. With the aim to obtain predictive ultimate load design formulas, a novel classication of laminate here proposed will be argued and related to a MhBT design formula. The in influence of peel and shear stresses interaction on the ultimate strength of the system has been discussed in detail.

2018 - Parameter identification of degrading and pinched hysteretic systems using a modified Bouc–Wen model [Articolo su rivista]
Pelliciari, M.; Marano, G. C.; Cuoghi, T.; Briseghella, B.; Lavorato, D.; Tarantino, A. M.
abstract

The Bouc–Wen (BW) model is a successful differential equations model used to describe a wide range of nonlinear hysteretic systems. However, it is unable to describe force degradation, stiffness degradation and pinching effects. Therefore, Baber and Noori proposed a generalisation, developing the Bouc–Wen– Baber–Noori (BWBN) model. Nevertheless, it is composed of many parameters and complex pinching and degrading functions. Thus, it is necessary to develop a simpler and reliable model to be used for practical applications. In this paper, a modified BW model is proposed. It involves a more direct physical meaning of each parameter and allows achieving a substantial reduction of computational effort and numerical deficiencies. This is obtained through simpler pinching and degrading functions that entail a decrease of the number of parameters. The result is a straightforward model, capable of predicting the behaviour of degrading and pinched hysteretic systems. An application of the proposed scheme to a real case is also presented, in which reinforced concrete bridge piers that were physically tested in the laboratory are considered. The force–displacement data are used to perform the identification process of the model parameters via a Genetic Algorithm. The numerical results are accurate since they coincide with the experimental ones.

2018 - Safety Assessment of Historic Timber Structural Elements [Articolo su rivista]
Barozzi, G.; Cosentino, N.; Lanzoni, L.; Tarantino, A. M.
abstract

Dealing with the safety assessment of existing buildings engineers often have to face the diagnosis of old timber structures. The current standards framework does not provide clear prescriptions about the evaluation of these kinds of structures, so the principal aim of this work is to outline an alternative methodology that leaves the concept of "Knowledge Level" and "Condence Factor", usually applied for existing buildings. An experimental campaign carried out on old timber joists supplied a sample of homogeneous data that were the support to the theoretical reasoning.

2018 - Severely damaged reinforced concrete circular columns repaired by turned steel rebar and high-performance concrete jacketing with steel or polymer fibers [Articolo su rivista]
Xue, J.; Lavorato, D.; Bergam, A. V.; Nuti, C.; Briseghella, B.; Marano, G. C.; Ji, T.; Vanzi, I.; Tarantino, A. M.; Santini., S.
abstract

2018 - Simple and effective models to predict the compressive and tensile strength of HPFRC as the steel fiber content and type changes [Articolo su rivista]
Savino, Vincenzo; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

HPFRC/UHPC are today widely applied as repair and reinforcement materials for structures. One of the drawback of commercial HPFRC/UHPC is that any modification of the matrix-fibers mix design, due to the market requirements, affects the mechanical properties of the hardened concrete and therefore the data obtained testing the previous version of the concrete are useless. Prediction models that link the properties of bothfibers and matrix to the performances of the hardened concrete are of great practical interest. This paper present a simple and effective model to account for the effect offibers on the compressive and tensile strengths of HPFRCs as the aspect ratio and volume offibers changes, extending the range of application of the few existing models.

2018 - Tensile constitutive behavior of high and ultra-high performance fibre-reinforced-concretes [Articolo su rivista]
Savino, Vincenzo; Lanzoni, L.; Tarantino, A. M.; Viviani, M.
abstract

High Performance Fibre-Reinforced-Cement-Composites and Ultra-High Performance Fibre-ReinforcedConcretes, also named HPFRCCs and UHPFRCs respectively, are today widely used as repair and strengthening existing structures, such as bridge decks, pavements, piers etc. Simple test methods to characterize its mechanical behavior are requested, in order to ensure that the product meets the designer’s requirements, especially in term of tensile behavior. Various test methods are available, even though a proper correlation between direct and indirect tensile (e.g. flexural) tests is needed. In this paper a model based on the ‘‘Composite Material Theory” (CMT) was developed to predict the flexural behavior of three commercialized SFRCs once the direct tensile strength is measured. A good agreement was found between experimental results and the values predicted by the model.

2017 - Degrading bouc-wen model parameters identification under cyclic load [Articolo su rivista]
Marano, G. C.; Pelliciari, M.; Cuoghi, T.; Briseghella, B.; Lavorato, D.; Tarantino, A. M.
abstract

The purpose of this article is to describe the Bouc-Wen model of hysteresis for structural engineering which is used to describe a wide range of nonlinear hysteretic systems, as a consequence of its capability to produce a variety of hysteretic patterns. This article focuses on the application of the Bouc-Wen model to predict the hysteretic behaviour of reinforced concrete bridge piers. The purpose is to identify the optimal values of the parameters so that the output of the model matches as well as possible the experimental data. Two repaired, retrofitted and reinforced concrete bridge pier specimens (in a 1:6 scale of a real bridge pier) are tested in a laboratory and used for experiments in this article. An identification of Bouc-Wen model's parameters is performed using the force-displacement experimental data obtained after cyclic loading tests on these two specimens. The original model involves many parameters and complex pinching and degrading functions. This makes the identification solution unmanageable and with numerical problems. Furthermore, from a computational point of view, the identification takes too much time. The novelty of this work is the proposal of a simplification of the model allowed by simpler pinching and degrading functions and the reduction of the number of parameters. The latter innovation is effective in reducing computational efforts and is performed after a deep study of the mechanical effects of each parameter on the pier response. This simplified model is implemented in a MATLAB code and the numerical results are well fit to the experimental results and are reliable in terms of manageability, stability, and computational time.

2017 - Effective thermal properties of fibre reinforced materials [Relazione in Atti di Convegno]
Lanzoni, L.; Radi, E.; Tarantino, A. M.
abstract

The thermal behaviour of an elastic matrix reinforced with synthetic micro or macro fibres subjected to a constant heat flow is investigated in the present work. Steady-state condition for the heat flux is considered and isotropic thermal conductivity for both the matrix and fibres is assumed. Owing to the geometry of the system, reference is made to bipolar cylindrical coordinates. Various boundary conditions can be considered on the contours of the fibres. In particular, for a matrix reinforced with two fibres taken as insulated inclusions, a vanishing heat flow across the contour of the fibres must be imposed. After the temperature field has benn determined analytically, a homogeneization procedure is performed in order to find the equivalent thermal properties of the fibre reinforced composite material.

2017 - On the edge-wave of a thin elastic plate supported by an elastic half-space [Relazione in Atti di Convegno]
Nobili, A.; Kaplunov, J.; Radi, E.; Tarantino, A. M.
abstract

In this contribution, we consider edge-wave propagating in a thin elastic semiinfinite plate which is bilaterally supported by a homogenenous isotropic elastic half-space. The problem is formulated in terms of a eigenproblem constituted by a system of five linear PDEs in the plate transverse displacement and in the scalar and vector elastic potentials subject to mixed boundary conditions accounting for plate-fundation displacement continuity under the plate and zero normal stress outside. Zero tangential stress is envisaged throughout. The problem could be reduced to an inhomogenenous Wiener-Hopf functional equation in terms of the half-space surface displacement and of the plate-to-fundation contact pressure only. The kernel function is analyzed and the Rayleigh wave speed is obtained together with a novel dispersion equation. Finally, kernel factorization is performed.

2017 - Structural Modelling at the Micro-, Meso-, and Nanoscales [Articolo su rivista]
Tarantino, A. M.; Kaplunov, J.; Luciano, R.; Majorana, C.; Rousakis, T. c.; William, K.
abstract

editorial

2017 - Ultra-high-performance fibre-reinforced concrete jacket for the repair and the seismic retrofitting of Italian and Chinese RC bridges [Relazione in Atti di Convegno]
Lavorato, D.; Bergami, A. V.; Nuti, C.; Briseghella, B.; Xue, J.; Tarantino, A. M.; Marano, G. C.; Santini, S.
abstract

The seismic behavior of Chinese RC (Reinforced Concrete) bridge piers with insufficient seismic details, severely damaged after an earthquake and then repaired and retrofitted by rapid interventions is investigated. The proposed interventions are applied on the damaged steel rebar and concrete parts in plastic hinge zone to guarantee the proper plastic dissipation of the seismic energy and the necessary shear strength and ductility improvements. New longitudinal shaped rebars and concrete jackets are used to substitute the pier damaged parts. Two repair and retrofitting procedures are presented and applied on 1:6 scaled pier specimens designed on the base of Chinese codes [1]-[3]: the first one uses an self-compacting concrete to build the concrete jacket and carbon Fiber Reinforced Polymer (CFRP) wrapping to assure the seismic improvements; the second one uses an ultra-high performance fiber reinforced concrete (UHPFRC) with steel fiber to build the concrete jacket and to assure the seismic upgrading allowing time and cost saving. The results of the first experimental tests on 1:6 scaled pier specimens repaired and retrofitting by the two procedures, are compared and discussed.

2016 - A RAPID REPAIR AND RETROFITTING INTERVENTION FOR SEISMIC DAMAGED CHINESE BRIDGE USING FIBER REINFORCED CONCRETE SHAPED REBAR AND EXTERNAL CFRP OR STEEL WRAPPING [Relazione in Atti di Convegno]
Lavorato, D.; Bergami, A. V.; Nuti, C.; Briseghella, B.; Tarantino, A. M.; Santini, S.
abstract

A rapid repair and retrofitting technique applied on reinforced concrete (rc) bridges damaged after a strong earthquake, can be a very effective solution to guarantee the use of the bridge for the emergency response in short time. This repair intervention makes possible a proper plastic dissipation distribution on the rebars in plastic hinge only and increases the original insufficient shear strength minimizing the intervention time and cost. In this paper, the technique was applied on the most damaged pier of an irregular rc bridge designed according to Chinese codes (JTG D60-2004, JTG D62-2004 and JTG/T B02-012008) but with insufficient transversal steel reinforcement. The rc pier repair operations consist in: substitution of the original damaged rebar parts by shaped rebar; restoration of the damaged concrete parts by concrete with fibers in plastic hinge only. In particular, this research focuses on the use of fiber concrete to increase the insufficient original shear strength and ductility of the pier. Compression and flexural tests on fiber concrete specimens were performed to determine the variation of the concrete mechanical properties with different fiber contents. Furthermore, the shear strength of the repaired pier specimen was evaluated by CNR-DT 204/2006 formulations considering the contribution of the new and of the original concrete parts. Finally, some pier specimens (scale 1: 6) were repaired using different concrete mixture with different fiber contents to prove the feasibility of the intervention in situ.

2016 - A simple nonlinear model to simulate the localized necking and neck propagation [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with the equilibrium problem in nonlinear dissipative inelasticity of damaged bodies subject to uniaxial loading and its main purpose is to show the interesting potentialities offered by the damage theory in modeling the necking and neck propagation phenomena in polymeric materials. In detail, the proposed mechanical model is a two-phase system, with the same constitutive law but with different levels of damage for each phase. Despite its simplicity, it is shown that the model can straightforwardly reproduce the overall load–elongation curve provided by experimental tensile tests by involving only five parameters of clear physical meaning.

2016 - Concrete beams stiffened by polymer-based mortar layers: experimental investigation and modelling [Articolo su rivista]
Lanzoni, Luca; Soragni, Marco; Tarantino, Angelo Marcello; Viviani, M.
abstract

In the present work, the main results provided by an experimental investigation, assessing the mechanical performances of concrete elements stiffened by a single or more layers of different kinds of polymer- modified cementitious repair mortar, are presented. The study is aimed in order to investigate the failure mechanism occurring in the samples under bending loading. In particular, the experimental investigation allows checking if the collapse mechanism is driven by delamination occurring along the interface among the overlays or by cracks propagating from the tensile region to the compressive zone, as it occurs in a typical failure mechanism driven by flexure. Thirty-eight precast and pre-stressed concrete samples were realized and cured to simulate load-bearing concrete ceiling beams widely employed as floor systems for residential buildings. After curing, the samples were subjected to three-point loading bending tests in order to evaluate the mechanical response of the specimens in terms of load vs. mid-span transverse dis- placement. Through the experimental tests, the crack initiation and propagation during the bending load- ing have been also investigated. Simplified finite element (FE) models were performed to properly reproduce the actual response of ceiling beams under non-symmetric loading bending. It is shown that the proposed FE model can be straightforwardly used to predict the behavior of concrete beams stiffened by polymer-based repair mortar layers.

2016 - Thin film bonded to elastic orthotropic substrate under thermal loading [Articolo su rivista]
Falope, FEDERICO OYEDEJI; Lanzoni, Luca; Radi, Enrico; Tarantino, Angelo Marcello
abstract

The problem of thin elastic films bonded on an elastic orthotropic substrate under thermal load is investigated in this work. Differently from past studies on the same topic, the effects induced by anisotropic behavior of the elastic substrate will be taken into account. Particular attention will also be paid to the determination of the displacement and stress fields induced by thermal loading. In particular, it is assumed that the thin films are deposed on the substrate at high temperature, and then the mismatch occurring during the cooling process, due to the difference between the thermal expansion coefficients of the two materials, is responsible for the permanent deformation assumed by the system. This phenomenon can be exploited for realizing a crystalline undulator. To this aim, the permanent deformation must be optimized in order to encourage the channeling phenomenon. By imposing equilibrium conditions and perfect adhesion between the film and the substrate, a singular integral equation is derived. A closed-form solution is achieved by expanding the interfacial shear stress fields in Chebyshev series. The unknown coefficients in the series expansion are then determined by transforming the integral equation into an infinite algebraic system.

2015 - Equilibrium configurations and stability of a damaged body under uniaxial tractions. [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with the equilibrium problem in nonlinear dissipative inelasticity of damaged bodies subject to uniaxial loading.

2015 - Pseudo-spectral methods in one-dimensional magnetostriction [Articolo su rivista]
Nobili, Andrea; Tarantino, Angelo Marcello
abstract

In this paper a pseudo-spectral method is proposed to solve a one-dimensional model of a saturated hard ferromagnetic thin-film structure within the Euler–Bernoulli kinematics. The model accounts for the non-local nature of the magneto-elastic coupling and interaction is in the form of a logarithmic potential. The proposed solution method adopts global polynomial interpolation at a main grid, given by the Gauss–Lobatto points, and it employs a secondary grid, consisting of the Gauss points, to perform the Gaussian quadrature. The two grids are non-overlapping to avoid the singularity. Interpolation relates the unknowns, evaluated at the secondary grid, to their values at the collocation grid. Furthermore, the integration interval is parted about the singularity point. The procedure is assessed through the relative equilibrium residual for different values of the approximating polynomial degree and of the quadrature order. Maximum, average and standard deviation of the error are presented. An asymptotic analysis yields the Boundary Solution to the problem and results are compared when the latter is introduced in the numerical scheme. It is shown that its contribution is important in reducing the overall error. The equilibrium residual is plotted and its behavior discussed. It is further shown that numerical precision significantly affects the results at midspan, owing to the self-equilibrium of the system, thereby a limit exists to the best accuracy which may be gained through a more accurate interpolation.

2014 - Assessment of stone columns as a mitigation technique of liquefaction-induced effects during Italian Earthquakes (May 2012) [Articolo su rivista]
Forcellini, D.; Tarantino, A. M.
abstract

Soil liquefaction has been observed worldwide during recent major earthquakes with induced effects responsible for much of the damage, disruption of function, and considerable replacement expenses for structures. The phenomenon has not been documented in recent time with such damage in Italian context before the recent Emilia-Romagna Earthquake (May 2012). The main lateral spreading and vertical deformations affected the stability of many buildings and impacted social life inducing valuable lessons on liquefaction risk assessment and remediation. This paper aims first of all to reproduce soil response to liquefaction-induced lateral effects and thus to evaluate stone column mitigation technique effectiveness by gradually increasing the extension of remediation, in order to achieve a satisfactory lower level of permanent deformations. The study is based on the use of a FE computational interface able to analyse the earthquake-induced three-dimensional pore pressure generation adopting one of the most credited nonlinear theories in order to assess realistically the displacements connected to lateral spreading. © 2014 Davide Forcellini and Angelo Marcello Tarantino.

2014 - Damaged hyperlastic membranes [Articolo su rivista]
Lanzoni, Luca; Tarantino, Angelo Marcello
abstract

This paper deals with equilibrium problems in nonlinear dissipative inelasticity of damaged membranes. The inelastic constitutive law is obtained by modifying the classical constitutive law for a hyperelastic isotropic material through a proper damage function, which allows to measure the effective stress and the dissipated energy. After making the constitutive modeling, the boundary-value problem is formulated for a damaged membrane subjected to biaxial loadings. The purpose of the analysis is to understand how behaves a membrane that, during the deformation process, experiences a progressively increasing damage. Equilibrium multiple branches of symmetric and asymmetric solutions, together to bifurcation points, are computed and it is shown how damage can alter these equilibrium paths with respect to the virgin undamaged case. In particular, the stress reductions caused by damage can give rise to transitions of the constitutive behavior from hardening type to the softening one. These changes can considerably affect the quality of the equilibrium solutions. Accordingly, the analysis is completed by assessing the stability of the solutions. For this aim, the stability analysis based on the energetic criterion is extended to damaged membranes.

2014 - Equilibrium paths of a hyperelastic body under progressive damage [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

This paper deals with equilibrium problems in nonlinear dissipative inelasticity, where inelastic effects are produced by the damage of the material. The inelastic constitutive law is obtained by modifying the classical constitutive law for a hyperelastic isotropic material through a damage function. To define this damage function, which allows to measure the effective stress and the dissipated energy, it is first used the Clausius-Duhem inequality, to have the (rate-independent) flow law of the damaged state and then it has been imposed a damage criterion based on an energy approach. After making the constitutive modeling, the boundary-value problem of the Rivlin's cube, now composed of damaged material, is formulated. The purpose is to analyze a three-dimensional body that, during the deformation process, experiences a progressively increasing damage. Equilibrium branches of symmetric and asymmetric solutions, together to bifurcation points, are computed. Emphasis is placed in investigating how the damage can alter these equilibrium paths with respect to the virgin undamaged case. In particular, the stress reductions caused by damage can give rise to transitions from hardening type to the softening one of the constitutive behavior. These changes can affect the quality of the equilibrium solutions. Accordingly, the analysis is completed by assessing the stability of the solutions. For this aim, the energetic method is extended to damaged materials.

2014 - Strato in misto cementato per pavimentazioni stradali [Brevetto]
Tarantino, Angelo Marcello; Nobili, Andrea; Grilli, Andrea; Lanzoni, Luca
abstract

Impiego di materiali fibrati per la realizzazione dei sottofondi stradali, allo scopo di ridurre la manutenzione.

2013 - Countermeasures assessment of liquefaction-induced lateral deformation in a slope ground system [Articolo su rivista]
D., Forcellni; Tarantino, Angelo Marcello
abstract

Liquefaction-induced lateral spreading may resul in significant damage and disruption of functionality for structures and slope groung system.

2013 - Experimental investigation and monitoring of a polypropylene-based fiber reinforced concrete road pavement [Articolo su rivista]
Nobili, Andrea; Lanzoni, L.; Tarantino, Angelo Marcello
abstract

In this work, basic guidelines are provided for the design of a polypropylene-based fiber reinforced (PFRC) road pavement.

2013 - Experimental investigation on fibre-reinforced cement-treated materials using reclaimed asphalt [Articolo su rivista]
A., Grilli; M., Bocci; Tarantino, Angelo Marcello
abstract

Cement treated material /CTMs) are used as base or subbase courses for heavy-traffic highway.

2013 - Liquefaction-induced lateral deformations computational assessment during Tohoku earthquake [Articolo su rivista]
F., Della Bartola; D., Forcellini; Tarantino, Angelo Marcello
abstract

Liquefaction-induced lateral spreading during Tohoku earthquake resulted in significant damage.

2012 - Performance evaluation of a polypropylene-based draw-wired fibre for concrete structures [Articolo su rivista]
Lanzoni, Luca; Nobili, Andrea; Tarantino, Angelo Marcello
abstract

Abstract. A polypropylene-based draw-wired fibre suitable for fibre reinforced concrete (FRC) is studied and its effect on flexural behaviour, toughness and shrinkage cracking is shown. In order to assess the perfor- mance offered by such a fibre over commercially available synthetic and metallic ones, comparative tests are carried out with respect to standard four-point bending and constrained shrinkage behaviour. The experimental evidence shows that FRC reinforced with these fibres possesses interesting structural fea- tures; in particular, fibres significantly improve crack resistance while enhancing toughness and durabil- ity of FRC elements. Equally important, such behaviour is gained without significantly affecting the workability of the mixture.

2011 - Teoria delle strutture con applicazioni [Monografia/Trattato scientifico]
Tarantino, Angelo Marcello
abstract

Questo testo di teoria delle strutture ha una indole prettamente didattica.

2009 - Introduzione alla meccanica delle strutture [Monografia/Trattato scientifico]
Tarantino, Angelo Marcello
abstract

Testo introduttivo alla meccanica dei solidi e delle strutture.

2008 - Homogeneous equilibrium configurations of a hyperelastic compressible cube under equitriaxial dead-load tractions [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

Non-uniqueness, bifurcation and stability of homogeneous solution to yhe equilibrium problem of a hyperlastic cube subject to equitriaxial dead-load tractions are investigated.

2008 - Magnetostriction of a hard ferromagnetic and elastic thin-film structure [Articolo su rivista]
Nobili, Andrea; Tarantino, Angelo Marcello
abstract

The magnetostriction of a thin film ferromagnetic and elastic structure is investigated.

2007 - A hard ferromagnetic and elastic beam-plate sandwich structure [Articolo su rivista]
Nobili, Andrea; Tarantino, Angelo Marcello
abstract

In this paper, the deformation of a composite hard ferromagnetic-elastic beam-plate structure is investigated. A sandwich structure, composed of two thin hard ferromagnetic layers, with a linear elastic lay-er in between, is considered. The deformation is due to the self generated magnetic field (magnetostriction). The aim is to assess the interaction forces among the perfectly bonded layers, through a consistent application of the classical nonlinear magneto-elastic theory. Once the general mechanical model is stated, the analysis is specialized to study longitudinal elongation, given its great relevance in technical applications. Owing to the non-local character of the magnetic action, a nonlinear integro-differential equation is derived. Some qualitative properties of the solution are pointed out and the asymptotic behavior near the end sections is examined in detail. A finite differences approach allows writing an approximating nonlinear system of equations in the non asymptotic part of the solution, which is solved through a Newton's iterative scheme. The numerical results are discussed and it is shown how the asymptotic part of the solution well approximates the full behavior of the structure. Furthermore, the longitudinal interaction force density is found to be singular at the end cross-sections, regardless of the assumed bonding type.

2007 - Finite homogeneous deformations of symmetrically loaded compressible membranes. [Articolo su rivista]
Tarantino, Angelo Marcello; Nobili, Andrea
abstract

The nonlinear equilibrium problem of hyperelastic square membranes, stretched by dead loads, is investigated.

2006 - Asymmetric equilibrium configurations of hyperelastic cylindrical bodies under symmetric dead loads [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The nonlinear equilibrium problem of cylindrical hyperelastic solids is investigated

2006 - Constitutive branching analysis of cylindrical bodies under in-plane equibiaxial dead-load tractions [Articolo su rivista]
Tarantino, Angelo Marcello; Nobili, Andrea
abstract

Finite homogeneous deformations of hyperelastic cylindrical bodies subjected to in-plane equibiaxial dead-load tractions are analyzed. Four basic equilibrium problems are formulated considering incompressible and compressible isotropic bodies under plane stress and plane deformation condition. Depending on the form of the stored energy function, these plane problems, in addition to the obvious symmetric solutions, may admit asymmetric solutions. In other words, the body may assume an equilibrium configuration characterized by two unequal in-plane principal stretches corresponding to equal external forces. In this paper, a mathematical condition, in terms of the principal invariants, governing the global development of the asymmetric deformation branches is obtained and examined in detail with regard to different choices of the stored energy function. Moreover, explicit expressions for evaluating critical loads and bifurcation points are derived. With reference to neo-Hookean, Mooney-Riviin and Ogden-Ball materials, a broad numerical analysis is performed and the qualitatively more interesting asymmetric equilibrium branches are shown. Finally, using the energy criterion, a number of considerations are put forward about the stability of the computed solutions. (C) 2006 Elsevier Ltd. All rights reserved.

2005 - Crack propagation in finite elastodynamics [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

Within the framework of finite elastodynamics, a crack propagation analysis, for sheets of compressible hyperelastic material, is formulated. By exploiting a dynamic generalization of the Stephenson's result, general far-field loading conditions are considered. Through an asymptotic singular analysis, the motion and the stress fields around a dynamically moving crack tip are then computed. Emphasis is placed on the order of singularity in the asymptotic Piola-Kirchhoff and Cauchy stresses, on the determination of crack profile and of the vector energy flux at the moving crack tip. Moreover, the most important differences with respect to the classical predictions of linear elastodynamic theory are evidenced.

2005 - Scienza delle Costruzioni, introduzione alla teoria dell’elasticità [Monografia/Trattato scientifico]
Tarantino, Angelo Marcello
abstract

Il testo contiene l'analisi della deformazione, della tensione, i lavori virtuali, i legami costitutivi, i principi variazionali e il problema dell'equilibrio di solidi a comportamento elastico non lineare e linearizzato.

2005 - Unilateral contact problem for aging viscoelastic beams [Articolo su rivista]
Nobili, Andrea; Tarantino, Angelo Marcello
abstract

The frictionless unilateral contact problem of a viscoelastic Bernoulli-Euler beam resting on a viscoelastic soil is studied. The mathematical formulation involves equilibrium equations, compatibility equations, and constitutive laws, with an aging integral-type form. The unilateral nature of the contact is imposed through a compatibility inequality, which allows the determination of the contact imprint at each time. Further, the governing integro-differential equation for the unknown contact pressure is derived. As special cases, the elastic Winkler-type soil and the rigid soil conditions are discussed. A numerical approach is presented, which employs the finite difference method along space and an adaptive step-by-step algorithm along time. The procedure allows for time discontinuities of both external loads and contact pressure. Several selected numerical examples are. presented and the influence of the most important material and geometrical parameters are shown. For the simplest situations, it was possible to compare the results obtained with known analytical solutions.

2002 - Asymmetric equilibrium configurations of symmetrically loaded isotropic square membranes [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The homogeneous deformations provided by the equilibrium problem of nonlinear isotropic hyperelastic symmetrically loaded membranes are analyzed. Besides the universal symmetric solutions, the problem considered, depending on the form of the stored energy function, may admit asymmetric solutions. For general incompressible materials, the mathematical conditions governing the global development of these asymmetric solutions are investigated. Explicit expressions for evaluating critical loads and bifurcation points are derived. Results and basic relations obtained for general isotropic materials are then specialized for a Valanis-Landel and an Ogden material. For this last case, which is frequently used to model rubberlike materials, a broad numerical analysis was performed. The more qualitatively interesting branches of asymmetric equilibria are shown and the influence of the material parameters is discussed. Finally, using the energy criterion a number of considerations are made on stability.

2002 - Meccanica dei materiali e delle strutture [Monografia/Trattato scientifico]
Cannarozzi, M.; Tarantino, Angelo Marcello
abstract

Introduzione alla meccanica dei materiali e delle strutture

2001 - Dynamic crack propagation in sheets of compressible neo-Hookean material under general in-plane loading [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The dynamic crack propagation in sheet of compressible neo-Hookean material is investigated.

2001 - Time-dependent analysis of shear-lag effect in composite beams [Articolo su rivista]
Dezi, L; Gara, F; Leoni, G; Tarantino, Angelo Marcello
abstract

Taking into account the long-term behavior of the concrete, a model for analyzing the shear-lag effect in composite beams with flexible shear connection is proposed. By assuming the slab loss of planarity described by a fixed warping function, the linear kinematics of the composite beam is expressed by means of four unknown functions: the vertical displacement of the whole cross section; the axial displacements of the concrete slab and of the steel beam; and the intensity of the warping (shear-lag function). A variational balance condition is imposed by the virtual work theorem for three-dimensional bodies, from which the local formulation of the problem, which involves four equilibrium equations with the relevant boundary conditions, is achieved. The assumptions of linear elastic behavior for the steel beam and the shear connection and of linear viscoelastic behavior for the concrete slab lead to an integral-differential type system, which is numerically integrated. The numerical procedure, based on the step-by-step general method and the finite-difference method, is illustrated and applied to an example of practical interest.

2000 - Creep analysis for structures with variable statical scheme: a unified approach [Articolo su rivista]
Chiorino, M. A.; Dezi, L.; Tarantino, Angelo Marcello
abstract

The problem of structural system change is analyzed for the most common practical situations.

2000 - Creep analysis of structures with variable statistical scheme-unified approach [Relazione in Atti di Convegno]
Chiorino, M. A.; Dezi, L.; Tarantino, A. M.
abstract

Variation of statistical scheme of reinforced and prestressed concrete structures is frequent in modem construction techniques. Construction sequences may include application of permanent loads and of prestressing in one or more steps, and connection of different portions of the structure, or introduction of additional restraints (sometime forcedly applied to correct the intemal stress conditions), at different ages during or after the construction process. The resulting stress distribution is largely influenced by the time-dependent deformability of concrete. The paper presents a unified approach for its evaluation based on the linear theory of viscoelasticity for aging materials, which is normally adopted for modeling concrete creep, evidencing the important role played by the non-dimensional redistribution function (1.111 t) describing the creep induced stress variation at timet for loading at 10 and variation of restraint conditions at t r The obtained solutions are exact for all problems of variation of restraint conditions in homogeneous structures with rigid restraints, and normally sufficiently accurate for problems concerning structures characterized by heterogeneities in the properties of concrete along their structural configuration. Redistribution function may be computed from the creep function J characterizing the creep prediction model under consideration and made available in tem1s of design aids (graphs or tables). The computational procedure is illustrated and an example of application to a typical structural problem is presented.

1999 - Homoclinic and heteroclinic bifurcations in the nonlinear dynamics of a beam resting on an elastic substrate [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

The nonlinear dynamics of a slender elastica resting on an elastic substrate is investigated.

1999 - On the finite motions generated by a mode I propagating crack [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The motion field surrounding a rapidly propagating crack, loaded symmetrically about the plane of the crack, is investigated. The problem is formulated within the framework of finite elastodynamics for thin slabs composed of compressible hyperelastic material. Writing the motion equations, the initial and the internal boundary conditions, with respect to a coordinate system that translates with the moving crack tip, we perform an asymptotic local analysis for a traction-foe straight crack that suddenly grows at constant velocity. Moreover, the asymptotic Piola-Kirchhoff and Cauchy stress Fields are computed, and we discuss the order of singularity of the dynamic stresses.

1999 - The singular wedge problem in the nonlinear elastostatic plane stress theory [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

A finite elastostatic analysis of the singular equilibrium field in the proximity of the apex of a wedge, with clamped-free radial edges and general far-field loading conditions, is performed. The problem is formulated for compressible hyperelastic sheets under a plane stress condition. An asymptotic procedure is proposed to compute the deformation and stress singular fields. Emphasis is placed on the investigation of the dependence of the order of singularity in the asymptotic Piola-Kirchhoff and Cauchy stresses on the wedge angles. The case of a half-plane bounded to a rigid substrate is studied in detail.

1998 - Creep and shrinkage analysis of composite beams [Articolo su rivista]
Dezi, L.; Leoni, G.; Tarantino, Angelo Marcello
abstract

articolo su invito

1998 - On extreme thinning at the notch-tip of a neo-hookean sheet [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The singular deformation and stress fields at the apex of a neo-Hookean sheet are investigated.

1997 - Anisotropic polynomial constitutive equations for electroelastic crystals [Articolo su rivista]
A., Danescu; Tarantino, Angelo Marcello
abstract

The constitutive equations for piezoelastic materials are derived.

1997 - Nonlinear fracture mechanics for an elastic Bell material [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

A crack analysis is performed for a Bell material.

1997 - The singular equilibrium field at the notch-tip of a compressible material in finite elastostatics [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

A crack nonlinear analysis is performed for compressible materials

1996 - Algebraic methods for time-dependent analysis of composite beams [Articolo su rivista]
Dezi, L.; Leoni, G.; Tarantino, Angelo Marcello
abstract

The algebraic viscoelastic methoda are applied for composite beams with flexible shear connectors

1996 - Approximate expressions for the ageing coefficient and the relaxation function in the viscoelastic analysis of concrete structures [Articolo su rivista]
Lacidogna, G.; Tarantino, M.
abstract

Creep analysis of concrete structures meets well-known computational difficulties when one needs to determine the relaxation function corresponding to a specified creep function through the inversion of Volterra's linear integral equation. For this reason, the recent proposals for the 1990 edition of the CEB Model Code introduce an approximate formulation of the relaxation function obtained from the expression of the ageing coefficient χ(t, t0) of the algebraic age-adjusted-effective modulus (AAEM) method assumed as a function of age at loading, t0, only. In the first part of this paper, an approximate algebraic expression, χ + ̃ for the ageing coefficient with reference to the MC 90 is presented. This formulation differs from previous proposals in that, in addition to the influence of t0, it also takes into account the influence of other parameters, such as relative humidity, characteristic strength of concrete and effective thickness. In the second part, this approximate algebraic expression of the ageing coefficient is used to obtain an approximate formulation for the relaxation function which is in very good agreement with the exact values of the relaxation function as obtained from the creep function through the solution of the basic integral equation. Finally, an example of structural calculation is provided (by applying the AAEM method and comparing the values obtained with those yielded by the general numerical method): the example clearly shows the advantages offered by the new approximate formulation of the ageing coefficient, χ + ̃, compared to the expression proposed in the CEB MC 90.

1996 - Chaotic dynamics of an elastic beam resting on a winkler-type soil [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

A nonlinear dynamics analysis of a slender elastica is performed.

1996 - Dynamics of shallow elastic arches. Part I: Chaotic response of harmonically shaped arches [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

A nonlinear dynamical analysis is performed for shallow elastic arches

1996 - Dynamics of shallow elastic arches. Part II: Optimal forms [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

The optimal forms for elastic arches under dynamics actions are studied.

1996 - Electro-elastic interactions and second order anisotropic constitutive equations [Articolo su rivista]
Danescu, A.; Tarantino, Angelo Marcello
abstract

The second order constitutive law for piezolestic materials are derived

1996 - Thin hyperelastic sheets of compressible material: field equations, Airy stress function and an application in fracture mechanics [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

Field equations and analysis of hyperelastic sheets are studied

1995 - A direct formulation for the stretch tensor [Articolo su rivista]
Governatori, P.; Menditto, G.; Tarantino, Angelo Marcello
abstract

Some properties of the stretch tensor are investigated.

1995 - Bifurcation and chaos in a bilinear constrained column. Part I: Stability analysis and nonlinear dynamics [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

The problem of an axially loaded compressed elastic column is studied.

1995 - Bifurcation and chaos in a bilinear constrained column. Part II: Chaotic dynamics [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

The nonlinear dynamics of a compressed column is investigated.

1995 - Method for analyzing complex viscoelastic structures [Articolo su rivista]
Chienna, G.; Dezi, L.; Tarantino, Angelo Marcello
abstract

A method for analyzing complex viscoelestic structures is proposed.

1995 - Modified AAEM method for composite beams with post-connected slab [Articolo su rivista]
Dezi, L; Leoni, G.; Tarantino, Angelo Marcello
abstract

The algebraic methods of viscoelasticity are applied for composite beams with prestressed slabs.

1995 - Time-dependent analysis of prestressed composite beams [Articolo su rivista]
Dezi, L.; Leoni, G.; Tarantino, Angelo Marcello
abstract

A viscoelastic analysis is performed for composite prestressed beams.

1995 - Viscoelastic heterogeneous structures with variable structural system [Articolo su rivista]
Dezi, L.; Menditto, G.; Tarantino, A. M.
abstract

1994 - Creep in composite continuous beams. II: Parametric study [Articolo su rivista]
Dezi, L.; Tarantino, A. M.
abstract

1994 - Influence of the excitation shape in the classical Duffing equation [Articolo su rivista]
Lenci, S.; Tarantino, Angelo Marcello
abstract

Some aspects regarding the shape of the excitation used to model a nonlinear oscillator are studied

1994 - Simplified creep analysis of composite beams with flexible connectors [Articolo su rivista]
Dezi, L.; Ianni, C.; Tarantino, A. M.
abstract

1994 - Structural system changes by means of forcedly applied restraints [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

Structural system changes by means of delajed restraints applied forcedly are studied.

1994 - The chaotic resonance [Articolo su rivista]
Lenci, S.; Menditto, G.; Tarantino, Angelo Marcello
abstract

The concept of chaotic resonance is proposed for elastic systems.

1993 - Creep in composite continuous beams I: theoretical treatment [Articolo su rivista]
Dezi, Luigino; Tarantino, Marcello
abstract

In this first part of the paper, the viscoelastic analysis of composite steel-concrete continuous beams with flexible shear connectors is performed. The method proposed evaluated the stress redistribution between the concrete slab and the steel beam, and the evolution of the redundant restrain reactions, which occur with time as a result of creep and shrinkage of the concrete part. The effects produced both by geometric and static actions are considered. The mathematical formulation of the problem involves the equations of equilibrium, internal and external compatibility conditions and constitutive relationships. i.e. an elastic law for the steel part and an integral-type creep law for the concrete part. Thus, the problem for a continuous beam with r redundant reactions is governed by a coupled system of r + 5 equations, of which two are integral-differential-type equations. Successively, this system is resolved by numerical step-by-step techniques. Therefore, performing two standard discretizations, in time and along the beam axis a numeric algorithm is proposed.

1993 - Creep in continuous composite beams. Part I: Theoretical treatment [Articolo su rivista]
Dezi, L.; Tarantino, Angelo Marcello
abstract

Continuous composite beams under statical and geometrical axternal actions are investigated.

1993 - Creep in continuous composite beams. Part II: Parametric study [Articolo su rivista]
Dezi, L.; Tarantino, Angelo Marcello
abstract

A parametric analysis is performed for continuous composite beams showing the creep effects.

1993 - Simplified creep analysis of composite beams with flexible shear connectors [Articolo su rivista]
Dezi, L; Ianni, C.; Tarantino, Angelo Marcello
abstract

Agebraic viscoelstic methods are applied for composite beams.

1993 - The contact problem for a class of orthotropic elastic solids [Articolo su rivista]
Menditto, G.; Quattrini, L.; Tarantino, Angelo Marcello
abstract

The solution of the contact problem for ortotropic materials is derived.

1993 - Viscoelastic heterogeneous structures with variable structural system [Articolo su rivista]
Dezi, L.; Menditto, G.; Tarantino, Angelo Marcello
abstract

The effects of the viscoelastic heterogeneities on structures under successive structural system changes are investigated.

1992 - Creep effects in composite beams with flexible shear connectors [Articolo su rivista]
Dezi, L.; Tarantino, Angelo Marcello
abstract

A viscoelastic analysis is performed for composite beams with flexible shear connectors.

1992 - Homogeneous structures subjected to repeated structural system changes [Articolo su rivista]
Dezi, L.; Menditto, G.; Tarantino, A. M.
abstract

1992 - Nonasymptotic solution for antiplane cracks [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

The non-asymptotic solution for un antiplane crack is obtained.

1992 - Prevention of stress relaxation in viscoelastic structures [Articolo su rivista]
Tarantino, Angelo Marcello
abstract

A new problem is presented in the viscoelastic theory. Structures where the stress relaxation is contrained are studied.

1991 - Applicazioni di teoria della frattura alla propagazione delle onde sismiche [Monografia/Trattato scientifico]
Tarantino, Angelo Marcello
abstract

Mediante la teoria della meccanica della frattura si studia la propagazione del moto ondoso prodotto da un sisma.

1991 - Time dependent analysis of concrete structures with variable structural system [Articolo su rivista]
Dezi, L.; Tarantino, Angelo Marcello
abstract

A integral relationship is presented for the immediate computation of the function governing the structural system change problem.

1990 - Homogeneous structures subjected to successive structural system changes - [Articolo su rivista]
L., Dezi; G., Menditto; Tarantino, Angelo Marcello
abstract

A viscoelastic analysis of structures subjected to successive structural system chages is performed.

1988 - Approximate calculation methods for solving problems of structures subjected to structural system changes [Articolo su rivista]
Dezi, Luigino; Tarantino, Angelo Marcello
abstract

After presenting the solutions to the problem of heterogeneous structures subject to changes of their structural system, obtained with the use of the main approximate methods, the reliability of the results is examined to compare these with those obtained with the application of the numerical step-by-step procedures of the General Method.

Università degli studi di Modena e Reggio Emilia

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