火灾后型钢混凝土框架结构力学性能试验研究及分析

EXPERIMENTAL RESEARCH AND ANALYSIS ON THE POST-FIRE PERFORMANCE OF STEEL REINFORCED CONCRETE FRAME STRUCTURES

考虑受火时间、荷载比等参数的影响,对火灾后型钢混凝土框架结构的破坏形态、变形性能以及剩余承载力等火灾后性能进行了试验研究。试验结果表明:火灾后型钢混凝土框架梁出现3个塑性铰而破坏,梁端弯剪变形明显,剪压区混凝土均出现部分脱落。随着受火时间的增加,型钢混凝土框架的剩余承载力逐渐减小。同时,建立了考虑升降温及火灾后全过程的火灾后型钢混凝土框架力学性能分析模型。计算结果与试验结果对比表明,二者吻合较好。可见,提出的模型是正确的。

An experiment was carried out to study the post-fire performance of steel reinforced concrete frame（SRCF） structures including the failure mode, deformability and residual load bearing capacity considering parameters including the fire duration and load ratio. The test results show that the failure of SRCF was induced by three plastic hinges occurred in the SRCF beam; the flexure-shear deformation was significant in the beam end; a part of concrete separated from the shear-compression zone of the frame beam. The results also show that the residual load bearing capacity of SRCFs decreases gradually with the increase of the fire duration. Based on the test, an analysis model for the post-fire performance of SRCFs under fire including heating, cooling and post-fire phases was proposed. The calculation results agree well with those of the test, which shows that the proposed numerical simulation method is accurate.