不同边界条件下采用半刚性节点三维组合楼板子结构连续倒塌行为试验研究

通过试验研究了4种不同拆柱位置采用半刚性节点大尺度三维组合楼板子结构的连续倒塌行为,对比分析了不同边界条件下三维组合楼板结构体系破坏模式和结构响应的异同,并对组合楼板的作用进行了量化分析。研究结果表明:失效柱位置不同时,结构的失效模式存在一定的差异;组合楼板的存在提高了结构的承载力,尤其是在大变形阶段更为显著;边界条件越强,组合结构抗连续倒塌性能越强;外部柱失效对结构抗连续倒塌产生的不利影响远远大于内部柱失效的情况,即当结构在外部柱失效情况下有足够的鲁棒性能,整体结构就不会发生连续倒塌。

Experimental study on progressive collapse behaviour of3D steel-concrete floor substructures with semi-rigidconnections under different boundary conditions

The progressive collapse behavior of three-dimensional (3D) steel-concrete floor substructures with semi-rigid connections was studied experimentally through four large-scale specimens under different columns removal scenarios. A comparison study was carried out to investigate the impact of boundary conditions on the failure modes and structural responses of 3D structural systems, and the contributions of the composite slab were quantitatively evaluated and discussed. The results show that the failure modes of the structures vary under different columns removal scenarios. The resistances of the composite floor structures are greatly enhanced due to the presence of composite slab, especially at large deformation stage. Structures with stronger boundaries conditions exhibit superior structural performance against progressive collapse. Compared with that under internal column removal scenarios, structures are more detrimental to progressive collapse after the failure of peripheral columns. This means progressive collapse would never occur if there is enough robustness under peripheral columns removal scenarios.