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.

Highly Dissipative Fiber-Reinforced Concrete for Structural Screeds / Signorini, Cesare; Sola, Antonella; Malchiodi, Beatrice; Nobili, Andrea. - In: JOURNAL OF MATERIALS IN CIVIL ENGINEERING. - ISSN 0899-1561. - 34:4(2022), pp. 1-13. [10.1061/(ASCE)MT.1943-5533.0004160]

Highly Dissipative Fiber-Reinforced Concrete for Structural Screeds

Signorini, Cesare
;
Sola, Antonella;Malchiodi, Beatrice;Nobili, Andrea
2022

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
21-gen-2022
34
4
1
13
Highly Dissipative Fiber-Reinforced Concrete for Structural Screeds / Signorini, Cesare; Sola, Antonella; Malchiodi, Beatrice; Nobili, Andrea. - In: JOURNAL OF MATERIALS IN CIVIL ENGINEERING. - ISSN 0899-1561. - 34:4(2022), pp. 1-13. [10.1061/(ASCE)MT.1943-5533.0004160]
Signorini, Cesare; Sola, Antonella; Malchiodi, Beatrice; Nobili, Andrea
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Licenza Creative Commons
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11380/1258721
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 8
  • ???jsp.display-item.citation.isi??? 9
social impact