基于不同基础模拟方式的钢-混凝土组合高架独柱车站抗震分析探讨

高架车站是一种"站桥合一"的结构,它既是建筑,也是轨道交通结构的一部分。对于独柱长悬臂高架车站而言,其结构抗震冗余度低,抗震分析尤为重要。钢-混凝土组合独柱车站结构是一种新型结构体系,其构件尺寸小,自重轻,有更强的抗震变形能力,它在地震作用下的具体表现值得研究。民用建筑设计规范和城市轨道交通设计规范对高架车站计算中的基础模拟有不同规定,有必要对不同基础模拟方式下的抗震分析结果进行探讨。通过具体的工程实例,建立多个比较分析模型,分析不同基础模拟方式之间的计算结果差异,给出设计建议。其一,由于独柱结构在地震作用下的扭转效应,需要特别关注边部构件的设计;其二,基于独柱结构的特殊性,设计应考虑桩土共同作用,对于土弹簧的不同取值应进行包络设计;其三,对于独柱结构的主要构件应进行抗震性能化设计,独柱墩的性能目标建议为大震斜截面弹性、正截面不屈服。

Seismic Analysis of Elevated Steel-concrete Composite Single Pillar Station Based on Models with Different Foundation Simulation

The elevated station is a combination structure of station and bridge,and it is a building and also a part of the rail transit structure. For elevated single pillar station with long cantilever,its seismic resistance redundancy is low and it is important to make seismic analysis. Steel-concrete composite single pillar station is a new kind of structure system,which has the advantages of small dimension of the members,light weight of the structure and strong deformation resistance. It is worth researching the performance of the steel-concrete composite single pillar station under earthquake. There are different requirements for foundation simulation according to code for structure design of building and code for design of urban rail transit structure. Therefore,it is necessary to discuss the seismic analysis results based on different foundation simulation methods. Different analysis models are built based on engineering projects. The differences of calculation results are compared and analyzed,and some suggestions for design are proposed. Firstly,due to the torsion effect of the single pillar structure under earthquake action,special attention should be paid to the design of side components. Secondly,based on the particularities of the single pillar structure,the design should consider the interaction of pile and soil,and envelope design should be carried out to obtain different stiffness values of soil spring. Thirdly,the main components of the single pillar structure should be designed for seismic performance,and the objective performance of the single pillar pier is suggested to be elasticity of the seismic oblique section and non-yield of the normal section.