复杂断面地下结构地震反应分析的整体式反应位移法

Integral response deformation method in seismic analysis of complex section underground structures

介绍地下结构抗震分析中常用的反应位移法存在的局限性,在借鉴反应位移法基本原理的基础上,提出一种适用于复杂断面地下结构地震反应分析的整体式反应位移法。从理论上论证该方法与反应位移法基本原理的一致性,详细介绍该方法的实施步骤与特点,给出地震作用的求解方法。该方法采用土-结构相互作用模型来直接反映土体与结构间的相互作用,避免了引入地基弹簧带来的计算量和计算误差。采用连续自由场土层模型来计算等效输入地震动荷载,概念明确、操作简单,能较好地适用于复杂断面地下结构的地震反应分析。结合实际工程与动力时程方法进行对比研究,结果表明,文中提出的整体式反应位移法是一个精度较高、计算简便、适用性很强的拟静力计算方法,可以用于地下结构的抗震分析与设计中。

Main problems of the response deformation method currently used for seismic respone analysisi of underground structures are discussed. Then based on the response deformation method, an integral response deformation method for complex section underground structures is proposed. The implementation procedure and features of the method are introduced in some details. Also included in the paper is a solution method of the earthquake loads which can reflect the soil-structure interactions under dynamic loading. The new method takes the soil-structure model to realize the interaction between soil and structure, and it takes the consecutive free-field soil model to calculate the equivalent earthquake load. The proposed method is of clear concept and easy for application. The method can be well applied in seismic analysis of the complex section underground structures. In order to verify the efficiency of the method, the integral response deformation and finite element dynamic analysis are conducted to calculate two actual subway station structures. The analysis results show that the integral response deformation method is more practical and suitable for seismic response analysis and design of underground structures.