SANTOS, Cristina Calmeiro dos; RODRIGUES, João Paulo C. - Experimental testing on the residual mechanical properties of ordinary concretes after fire. In International Conference on Experimental Mechanics, 15 Porto, 22-27 de julho 2012. [S.l.: s.n.], 2012. p 1-13
Title
Experimental testing on the residual mechanical properties of ordinary concretes after fire
Concrete is known to have an enhanced behaviour in fire when comparing with bare steel,
however there are some chemical and physical transformations in function of temperature that
may compromise this performance. The mechanical and thermal properties of concrete at high
temperatures and after fire have changes that have been evaluated in a lot of works around the
World, however this is still an open field where a lot of research is needed. This paper
summarizes the results of an experimental research to assess the residual mechanical
properties of ordinary concretes after fire. It was studied the influence of the fire
extinguishing methods, the maximum temperature that the concrete was subjected to and the
loading level on the residual mechanical properties of calcareous and granite aggregate
concretes. The properties studied were the residual compressive, tensile, splitting and flexural
strengths and modulus of elasticity. Four levels of temperature; 20ºC, 300ºC, 500ºC and
700ºC; two loading levels (0.3fcd and 0.7fcd) and two cooling processes (cooling in the air
and by water jet) were tested. The results showed that the mechanical properties of concretes
are affected by the cooling process (fire extinguishing methods) used beyond the high
temperatures and loading levels that were subjected to.