薄壁闭腔对装配式车站结构力学性能影响研究

Study on the Influence of Thin-walled Closed Cavity on the Mechanical Properties of the Prefabricated Subway Station

国内首例全预制装配式地铁车站采用薄壁闭腔构件代替传统实心构件,实现了装配式构件的轻量化。为了研究闭腔布设形式对装配式结构性能的影响,以装配式地铁车站单环结构为研究对象。分别对实心结构和空心结构在竖向荷载作用下的非线性力学与变形性能开展研究,得到了各结构的破坏形态和荷载位移曲线,并对结构应力、内力进行对比分析。分析表明:装配式结构整体具有较好的承载与变形能力。实心结构与空心结构具有相似的破坏形态。实心构件内设置闭腔,结构应力分布相对集中,承载能力与刚度降低。但空心构件的截面内力较小,延性性能更好。基于装配式结构绿色环保的设计理念,考虑到极限承载情况下结构的承载能力与变形能力,预制装配式车站选用空心构件且设置双排闭腔更符合要求。研究结论可为装配式地铁车站的深化研究和工程设计提供理论支撑与技术参考。

The first prefabricated subway station in China adopted the thin-walled closed cavity components instead of the traditional solid components,which realized the lightweight of the prefabricated components.In order to study the influence of the layout of the closed cavity on the performance of the prefabricated structure,we took the single-ring structure of the prefabricated subway station as the research object.The nonlinear mechanical and deformation performance of the solid and hollow structures under the vertical load was studied.The failure mode of each structures and the load-displacement curve of the structure were obtained,and the stress of the structure and the internal force of the cross-section were compared and analyzed.The results show that the prefabricated structure as a whole have better bearing and deformation performance.The solid structure and the hollow structure have similar failure patterns.After the closed cavity is set in the solid component,the stress distribution of the structure is relatively concentrated,meanwhile the bearing capacity and rigidity of the structure reduce.However,the internal force of closed-cavity components is smaller and its ductility is better.Based on the environmental protection design concept of prefabricated structure,taking into account the bearing capacity and deformation capacity of the structure under extreme load conditions,it is more suitable to install double rows of closed cavities in prefabricated components.The research conclusions can provide theoretical support and technical reference for the deepening research and engineering design of the assembled subway station.