54. Cementitious materials with hybrid fibers exposed to high temperatures

Title: 54. Cementitious materials with hybrid fibers exposed to high temperatures
Author(s): L. Biolzi, G.L. Guerrini, L. Bertolini
Paper category : conference
Book title: 6th International RILEM Symposium on Fibre Reinforced Concretes
Editor(s): M. di Prisco, R. Felicetti and G.A. Plizzari
Print-ISBN: 2-912143-51-9
e-ISBN: 2912143748
Publisher: RILEM Publications SARL
Publication year: 2004
Pages: 635 - 646
Total Pages: 12
Nb references: 18
Language: English

Abstract: Extreme environmental conditions, such as exposure to high temperatures, are serious potential risks for buildings and structures. The behavior of concrete, after exposure to a high temperature, depends upon the specific concrete mix proportions, the constituents used and the physicochemical transformations that the heating generates. Within this context, the damage, after thermal treatments, in cement-based matrices was studied using compression and three-point bending tests. Four types of high performance cement based composites were prepared using fiber combinations of polypropylene and steel fibers. Specimens were treated in an electric furnace at 250°C, 500°C and 750°C. The corresponding compressive and bending strengths were determined, and fracture behavior was studied using interferometric measurements. A physical analysis was also performed by the use of Mercury Intrusion Porosimetry (MIP) and microscopy observation (SEM). For the considered combinations, it was demonstrated that a hybrid mixture of steel and polypropylene fibers appears to be not particularly effective in enhancing the performance of concrete at high temperatures. With the considered heating rate, explosive spalling was not observed in concrete specimens during the thermal treatment, but a melting of steel fibers after the treatment at 750°C was detected.

Online publication: 2004-08-30
Publication type : full_text
Public price (Euros): 0.00