Thermal analysis of steel decking concrete slabs in case of fire

Abstract

The thermal behavior of composite steel-concrete slabs in fire is more or less known, however there are still a lot of different aspects in the fire design methods that need clarification. A comparison of the temperature distribution in the cross-section of steel decking concrete slabs subjected to fire is made through three different procedures: (a) experimental, (b) numerical and (c) analytical methods. The experimental tests corresponding to eight real-scale fire tests on slabs carried out by the authors. These tests have been used to calibrate numerical models for being used with the finite element software Abaqus. The analytical methods were the ones proposed in Annex D of EN 1994-1-2. The analytical steel decking temperatures showed convergence with the experimental and numerical ones. The same was not observed for the concrete, positive and negative rebar and thermal insulation temperatures. A new analytical approach for assessing the negative rebar temperatures and new factors for assessing the thermal insulation performance - alternative to EN 1994-1-2 - are proposed.