Fire spalling of concrete can seriously jeopardise the integrity of the entire structure due to the reduction of the cross-sectional area of the structural elements, which lead to direct exposure of reinforcing bars to flames. In the literature, it is shown that the occurrence of fire spalling is influenced by various parameters, the external compressive load being one of them, which role is not well known in detail. Within this context, an extensive experimental campaign has been conducted to investigate the interaction between pore pressure and thermo-mechanical stresses in triggering spalling. Mid-size concrete slabs (800 x 800 x 100 mm3) were exposed to ISO 834-1 fire curve at the bottom face, while an external membrane biaxial compressive stress was applied before heating parallel to the heated face of the slab. The experimental results have clearly shown that the loaded specimens are more prone to spalling than unloaded specimens, with increasing amounts of spalling for higher values of applied compressive stress. Spalling behaviour of B40-II (12% of calcareous filler and 3% of slag) and B40-III (43% of slag) appear similar.

Experimental investigation on fire spalling behaviour of concrete: effect of biaxial compressive loading and cement type

Francesco Lo Monte;Roberto Felicetti;
2017-01-01

Abstract

Fire spalling of concrete can seriously jeopardise the integrity of the entire structure due to the reduction of the cross-sectional area of the structural elements, which lead to direct exposure of reinforcing bars to flames. In the literature, it is shown that the occurrence of fire spalling is influenced by various parameters, the external compressive load being one of them, which role is not well known in detail. Within this context, an extensive experimental campaign has been conducted to investigate the interaction between pore pressure and thermo-mechanical stresses in triggering spalling. Mid-size concrete slabs (800 x 800 x 100 mm3) were exposed to ISO 834-1 fire curve at the bottom face, while an external membrane biaxial compressive stress was applied before heating parallel to the heated face of the slab. The experimental results have clearly shown that the loaded specimens are more prone to spalling than unloaded specimens, with increasing amounts of spalling for higher values of applied compressive stress. Spalling behaviour of B40-II (12% of calcareous filler and 3% of slag) and B40-III (43% of slag) appear similar.
2017
Proceedings from the 5th International Workshop on Concrete Spalling, Borås, Sweden, 12-13 October 2017 SP Report: 2017:43
standard fire, biaxial loading, spalling, pore pressure, cracking, displacement, cement.
File in questo prodotto:
File Dimensione Formato  
Full Paper_Slabs Jihad.pdf

Accesso riservato

Descrizione: Articolo principale
: Publisher’s version
Dimensione 2 MB
Formato Adobe PDF
2 MB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11311/1063767
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact