The Reliability Analysis of Reinforced Concrete Beams under High Temperature

For the mechanical properties of reinforced concrete under high temperature with large deterioration, the reliability of reinforced concrete beams have been largely discounted. The plastic zone resistance of concrete under high temperature has been considered in this paper. A simple and feasible time-variant model of the resistance of reinforced concrete beams has been given under fire and a reliability index analysis method of reinforced concrete beams under fire. The action of ISO834 temperature rising curve on the reliability index of different specifications of concrete beams at different time has been analyzed. The action of main parameters on the reliability index changes with time has been shown. The results have shown that the increase the reinforcement ratio and concrete cover thickness appropriately is an effective measure to improve the fire resistance limit of reinforced concrete beams.