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BEATRICE MALCHIODI
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Pubblicazioni
2023
- Three sustainable polypropylene surface treatments for the compatibility optimization of PP fibers and cement matrix in fiber-reinforced concrete
[Articolo su rivista]
Malchiodi, B.; Pelaccia, R.; Pozzi, P.; Siligardi, C.
abstract
2022
- A Practical Valorization Approach for Mitigating Textile Fibrous Microplastics in the Environment: Collection of Textile-Processing Waste Microfibers and Direct Reuse in Green Thermal-Insulating and Mechanical-Performing Composite Construction Materials
[Articolo su rivista]
Malchiodi, Beatrice; Siligardi, Cristina; Pozzi, Paolo; Iveth Cedillo-González, Erika
abstract
2022
- Char Valorization into Sustainable and Performant Polyurethane Insulating Panels
[Articolo su rivista]
Malchiodi, Beatrice; Barbieri, Luisa; Lancellotti, Isabella; Pozzi, Paolo
abstract
2022
- Green fiber reinforced cements containing recycled textile fibers from the finishing of fabrics
[Poster]
Malchiodi, Beatrice; Pozzi, Paolo; Siligardi, Cristina
abstract
2022
- Highly Dissipative Fiber-Reinforced Concrete for Structural Screeds
[Articolo su rivista]
Signorini, Cesare; Sola, Antonella; Malchiodi, Beatrice; Nobili, Andrea
abstract
Synthetic fibers, especially polypropylene (PP) fibers, are emerging as a viable reinforcement for concrete, on account of their excellent durability, affordability, anti-spalling capability, low density, and magnetic transparency. Yet, the chemical nature of PP hinders the development of strong bonds at the fiber-to-matrix interface, with negative effects on the mechanical performance. To overcome this difficulty, in this research fibers are either chemically attacked (etched) or coated through sol-gel nanosilica deposition in order to promote their affinity to the hydration products in the binder. Three-point bending tests at different scales are carried out on unnotched specimens, including large-scale beams consisting of PP-reinforced concrete for structural screeds. Functionalization, especially in the form of silica coating, improves the binder-fiber interaction, which is responsible for a remarkable increment in the specific energy dissipated at failure, with respect to untreated fibers. Most importantly, both surface treatments induce a substantial hardening response as opposed to the softening behavior that is characteristic of low-dosage fiber-reinforced concrete. We conclude that surface functionalization, and especially nanosilica coating, offers significant advantages for better exploiting the reinforcing effect of PP fibers, and these carry over at different scales. In particular, results appear promising for screeds, which advocate optimal mechanical performance and durability while keeping the fiber content to a minimum.
2022
- Influencing Parameters for the Failure Mechanism of Carbon-FRCM (Fibre Reinforced Cementitious Matrix Systems)
[Relazione in Atti di Convegno]
Malchiodi, Beatrice; Grana Castagnetti, Gabriele; Siligardi, Cristina
abstract
2022
- Optimization of Polyurethane Panels Properties through Different Particle and Fiber Reinforcement
[Articolo su rivista]
Malchiodi, Beatrice; Pozzi, Paolo
abstract
2022
- Recovery of Cork Manufacturing Waste within Mortar and Polyurethane: Feasibility of Use and Physical, Mechanical, Thermal Insulating Properties of the Final Green Composite Construction Materials
[Articolo su rivista]
Malchiodi, Beatrice; Marchetti, Roberta; Barbieri, Luisa; Pozzi, Paolo
abstract
The valorization of industrial waste is a hot topic toward circular economy and sustainability. Several wastes have been proposed as resources for different production processes; however, others are still disposed to landfill or waste-to-energy plants. For the first time, this work suggests a sustainable alternative to managing cork waste from bottle caps manufacturing; this is generated by a local company at about 220,000 m3/year. The powder waste has a 0.063–1 mm particle size and is mainly composed of cork, polyurethane adhesive, and paraffin. Its valorization is proposed as filler in construction materials such as lime-based mortar (1–4 wt%) and polyurethane (5–15 wt%). Thermal, spectroscopic, and physical characterizations are performed on the cork waste, and mainly result in a low apparent density (340 kg/m3) and high-water absorption (177%). Cork properties allow consideration of extra water in the mortar mix and improve lightness without significantly affecting compressive, bending strength, and thermal insulation. Cork waste in polyurethanes promotes a color change, slightly increases the density (up to 12.5%), and still results in producing a thermally insulating material (<0.06 W/mK). Considering the promising results, this study demonstrates the feasibility of using the manufacturing waste from cork bottle caps to produce green construction materials, thus upgrading it from waste to secondary raw material.
2022
- Unsaturated Polyester-Based Polymer Concrete Containing Recycled Cathode Ray Tube Glass Aggregate
[Articolo su rivista]
Malchiodi, Beatrice; Siligardi, Cristina; Pozzi, Paolo
abstract
Polymer concrete (PC) is a composite construction material that boasts several advantages, such as lightness, low water permeability, high resistance to corrosive environments, and chemical degradation. Consequently, it has recently attracted interest as an alternative material to the traditional ones for several civil applications. In this study, unsaturated polyester resin was considered the matrix phase of PC. Aimed to produce green PC, the commonly dispersed phase of natural aggregate was totally replaced by recycled glass aggregate (RGA) deriving from cathode ray tube (CRT) glass waste. Fine and coarse fractions of non-hazardous CRT glass were considered in different ratios. Chemical and physical analyses were carried out through XRF, particle size distribution and microstructural analysis to characterize RGA. The influence of RGA particle size and percentage on PC performance was investigated by microstructural analysis and aggregate packing, chemical resistance, water absorption, and mechanical analyses, such as bending, impact, and scratch test. Using solely the coarse fraction of RGA led to the manufacturing of a green PC with similar performance to the traditional PC and in addition lower in density. The PC quality mainly depended on the matrix crosslinking which, for PC containing fine RGA, was promoted by adding 4 wt% of silane coupling agent.
2021
- Dissemination "Notte dei ricercatori"
[Altro]
Malchiodi, Beatrice
abstract
“La notte dei Ricercatori, 24th September 2021”:
In person event aimed to show the research activities and main results of UNIMORE’s research groups. The candidate introduced the emerging topic of recycled raw materials and the sustainability of construction materials. During the event, Recycled Concrete Aggregate from Construction and Demolition Waste were displayed to the audience in different grain sizes as a result of a selective demolition procedure and of mechanical sieving. Then, the final application as a sustainable raw material for green concrete was demonstrated using a demonstrative concrete sample. A poster with the main characterization results of both recycled aggregate and green concrete was involved as technical support.
2021
- Dissemination "Robidone"
[Altro]
Malchiodi, Beatrice
abstract
“Robidone, 12th May 2021”:
interview by Robidone robot aimed to educate children and young students on waste recycling and construction materials' sustainability. The interview was recorded, and post-processing was performed to create a video lesson suitable for distribution to schools and online platforms.
2021
- Influencing parameters for the failure mechanism of carbon-FRCM (Fibre Reinforced Cementitious Matrix systems)
[Abstract in Atti di Convegno]
Grana Castagnetti, Gabriele; Malchiodi, Beatrice; Siligardi, Cristina
abstract
2021
- Materiali compositi sostenibili e a bassa trasmittanza termica: cementi contenenti microfibre tessili di riciclo
Sustainable and thermal nsulating composite materials:cements containing recycled textile m,icrofibres
[Articolo su rivista]
Malchiodi, Beatrice; Siligardi, Cristina; Pozzi, Paolo
abstract
L’impiego di materie prime di riciclo si impone come urgente ed attuale obiettivo per lo sviluppo di materiali da costruzione sostenibili. Tra i rifiuti non pericolosi generati dall’industria manifatturiera italiana, il 37.4% è derivante dal settore tessile e tra di essi si individuano sia rifiuti vestiari che fibre di scarto del processo produttivo. Si stima che la seconda tipologia venga prodotta in Italia nella misura di 5000ton/anno. In questo lavoro, si è valutato il riciclo di microfibre tessili derivanti da operazioni di finissaggio all’interno di impasti cementizi. L’inserimento in miscela del 4% di microfibre (60%cotone, 30%misto cotone, 10%sintetico) ha prodotto, rispetto al semplice cemento, un incremento del 400% della resistenza a flessione, una riduzione del 80% del ritiro ed il raddoppio del potere isolante termico. Si è, quindi, validato l’impiego di microfibre tessili di scarto per la produzione di compositi cementizi sostenibili ed a ridotta trasmittanza termica.
2021
- Use of recycled textile fibres for sustainable and thermal insulating Fibre Reinforced Cement
[Abstract in Atti di Convegno]
Malchiodi, Beatrice; Siligardi, Cristina; Pozzi, Paolo
abstract
Recycling and sustainability are hot topics for Civil applications. Since 37.4% of Italian non-hazardous waste comes from the textile field, many studies focused on their reuse. This work investigates the recovery of waste textile microfibres, deriving from finishing of fabrics, into sustainable and low conductive Fibre-Reinforced Cement (FRC). The microfibres are characterized through FTIR technique and Scanning Electron Microscopy; moreover, water content and water absorption are evaluated for mix design. Unsaturated, saturated and NaOH treated microfibres are considered. Following a preliminary workability evaluation, they are introduced in Portland cement in 1%, 2%, 3%, 4% by weight. At increasing fibre percentage, the three-point bending test displays an enhance from 1.5 to 4 times the maximum bending load of non-reinforced Portland and a marked increase in toughness is observed. The linear shrinkage is reduced from 20% to 80%, and NaOH microfibres result in more efficiency. Stereomicroscopy confirmed a high fibre dispersion into the cement matrix. A reduction in thermal conductivity is observed when increasing percentage of the untreated fibres, and for 4% fibre percentage the Portland insulation power is doubled. The feasibility of using recycled textile microfibre into FRC is demonstrated and results in improving sustainability, mechanical properties and power insulating.
2021
- Valorization of demolition concrete waste and tile waste into more sustainable structural concretes and grouts
[Poster]
Malchiodi, Beatrice; Siligardi, Cristina; Pozzi, Paolo
abstract
2020
- Failure mechanism of silica coated polypropylene fibres for Fibre Reinforced Concrete (FRC)
[Articolo su rivista]
Signorini, C.; Sola, A.; Malchiodi, Beatrice; Nobili, A.; Gatto, A.
abstract
This work investigates the effect of a fast, acid-catalysed sol-gel silica nano-coating on the mechanical performance of draw-wire Polypropylene (PP) fibres used as dispersed reinforcement in Fibre Reinforced Concrete (FRC). The failure mechanism is investigated. To this aim, the role of curing time is also considered. Mechanical performance is assessed in pull-out and three-point bending tests of un-notched beams. Coating deeply affects the post-cracking behaviour of FRC, which shifts from brittle (plain concrete), to softening (uncoated) and finally to plastic-softening (coated fibres). Remarkably, 28-day curing improves over 8-day curing in terms of energy dissipation capability for coated fibres only. This suggests that fibre-to-matrix bond enhancement moves the failure mechanism from delamination at the interface to failure in the interphase zone. In the former case, failure is inconsistent and occurs independently from the curing time while in the latter failure depends on the matrix quality.
2019
- Study of a porous magnesia-based cement
[Poster]
Malchiodi, Beatrice; Barbieri, Virginia; Eva Madgalena Lassinantti Gualtieri, ; Siligardi, Cristina; Manfredini, Tiziano
abstract