装配整体式地下车站侧墙开洞结构力学性能分析

Mechanical Performance Analysis of Side Wall Opening Structure in Assembled Monolithic Underground Station

当前侧墙开洞的研究主要集中在地上结构开洞墙体的整体受力性能,而对装配式地下车站侧墙开洞结构的研究还较少。综合考虑侧墙开洞结构受力及施工难易程度,接口框架分拆为梁和柱,节点设置在梁端。为确定侧墙开洞结构的力学性能,对设计方案进行了力学试验与数值模拟分析。研究结果表明:通道接口的破坏形态主要表现为洞口梁端的扭转斜裂缝,梁的扭转破坏是侧墙开洞结构失效的主要原因;侧墙开洞结构的刚度退化的主要原因是混凝土开裂,而构件中钢筋屈服的影响基本上可忽略不计;对侧墙开洞结构进行数值分析,可得到构件的内力分布;梁端的扭转承载力是侧墙开洞结构平面外承载力的主要部分。给出了洞口梁的扭转承载力建议公式,为装配整体式地下车站侧墙开洞结构的设计提供了参考依据。

Researches on side wall opening mainly focus on the overall mechanical performance of walls with opening structure above-ground,while few studies are on side wall opening structure in assembled monolithic underground station.Comprehensively considering the force condition of the opening structure and the difficulty level of construction,the interface frame is divided into beams and columns,and the nodes are set at the beam ends.In order to elucidate the mechanical performance of side wall opening structure,mechanical tests and numerical simulation analysis are carried out.Research results show that:the destruction morphology of the passage interface is mainly manifested as the torsional oblique crack at the ends of the beam.The torsion destruction of the beam is the main reason for side wall opening structure failure.The stiffness degradation of side wall opening structure is mainly due to concrete cracking,and effect from yield of the steel bar in component can be overlooked.By numerically analyzing side wall opening structures,internal force distribution of the components is obtained.The torsional bearing capacity at beam ends is the main factor of side wall opening structure out-of-plane bearing capacity.Recommended formula for the opening beam torsional bearing capacity is given,providing reference for the design of side wall opening structure in assembled monolithic underground station.