Effect of unprotected interior beams on membrane behaviour of composite floor system in fire, II: Numerical assessment

Authors

  • Tuan-Trung Nguyen
  • Kang-Hai Tan

Abstract

The authors’ companion paper presented the observations and results from two one-forth scale composite beam-slab systems tested in fire. This paper introduces the numerical assessment based on these experimental results. A non-linear finite element model is developed using ABQUS/Explicit to simulate the specimen behaviour. Material properties at elevated temperatures are assumed to vary according to EN 1994-1-2 (2005). The FE model was first validated with the test results, and then was used to examine the effect of unprotected interior beams on tensile membrane action. It is found that the numerical predictions agree well with the test results. The presence of interior beams significantly affects the magnitude as well as the distribution of stress of the slab elements, i.e. mesh reinforcement and concrete slab. The part with maximum tensile force is not necessarily at the slab centre. It may be part of the concrete slab above the edge beams. Shortcomings of the numerical model in predicting the failure modes are indicated.

Downloads

Published

2015-10-15