Experimental research and theoretical analysis on the post-fire mechanical#br#
performance of the continuous concrete slabs
Wang Yong1,2 Jiang Yaqiang1 Zhang Yajun1 Li Lingzhi1,3 Wu Jiachao1 Wang Gongchen1
1. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221008, China;
2. Jiangsu Collaborative Innovation Center for Building Energy Saving and Construction Technology, Xuzhou 221008, China;
3. Tongji University, Shanghai 200092, China
Abstract：To investigate the effect of the number and position of the fire-damaged spans on the post-fire behavior of the continuous concrete slabs, the strength tests on one reference slab and five fire-damaged slabs were carried out, and then the post-fire cracks, deflections, concrete and steel residual strains and failure modes were analyzed. Based on the yield line theory, the failure mode and elliptic equations of two-way concrete slab were proposed, and the equilibrium equations of internal forces were established to analyze the carrying capacities of the fire-damaged slabs. The comparison of analysis results between the present method and other methods was also conducted. Results show that different from the yield ductile failure mode of the reference slab, the fire-damaged slab easily tends to fail in the brittle failure mode, including the punching shear failure at the loading point or at the internal support, particularly the serious spalling case. Compared to the strain failure criteria of concrete and steel, the deflection failure criterion l/50 was suitable for determining the residual limit loads of the firedamaged slabs. In addition, the present method can be used to determine the residual limit carrying capacity of the fire-damaged slab, and the predicted results were relatively conservative. For the fire-damaged slab, the flexural theory and the punching shear theory shall be used to determine the residual carrying capacity of the fire-damaged slab respectively, and the minimum value can be regarded as the residual limit load.
王勇 姜亚强 张亚军 李凌志 吴加超 王功臣. 混凝土连续板火灾后力学性能试验及理论分析[J]. 土木工程学报, 2021, 54(3): 41-57.
Wang Yong Jiang Yaqiang Zhang Yajun Li Lingzhi Wu Jiachao Wang Gongchen. Experimental research and theoretical analysis on the post-fire mechanical#br#
performance of the continuous concrete slabs. 土木工程学报, 2021, 54(3): 41-57.
