考虑土—结构相互作用的能力谱法在桥梁抗震性能评估中的应用

发布时间：2018-03-01 15:43

本文关键词： 桥梁能力谱法需求谱损伤指标性能评价　出处：《兰州交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：桩构件及地基土的非线性特性对桥梁的抗震性能有着重要的影响，考虑土-结构相互作用下桥梁抗震性能的研究是目前桥梁抗震领域研究的一个热点。本文针对铁路桥梁的特点，，采用理论分析及数值模拟相结合的方法，系统研究了考虑土-结构相互作用下桩基桥墩的非线性性能，对考虑土-结构相互作用下桩基桥墩的抗震性能评估方法进行了研究，主要研究内容如下：（1）在深入研究现有的各种静力推倒模型的基础上，结合桩-土相互作用自身的特点，提出了考虑桩-土相互作用的非线性静力推倒模型。该模型可以同时考虑桩构件及地基土的非线性，能较好的模拟地震作用下结构和地基土的相互作用。（2）基于基于本文提出的群桩基础静力非线性计算模型，研究了桩基纵筋配筋率、配箍率、地基土参数、墩高及不同加载模式等因素对桩基桥墩承载特性及变形能力的影响，总结了桩身塑性铰的发展过程及分布特征。（3）研究了考虑桩-土相互作用下需求谱的折减，结合桩-土相互作用自身的特点，对目前存在的多种需求谱的折减方法进行了对比研究，结果表明Vidic折减模型及吕西林折减模型更适合于对考虑桩-土相互作用下需求谱的折减。（4）在对比研究ATC-40中提出的能力谱法、修正能力谱法、位移系数法、性能点轨迹法的基础上，通过参考文献[65]的研究成果，提出了本文求解性能点的方法，该法与性能点轨迹法的求解结果误差在6%以内。（5）在研究国内外各种规范及参考各种文献的基础上，并结合桩-土相互作用下桥墩墩顶位移明显增大的特点，提出了以墩顶位移角为损伤指标的桥梁抗震性能评价指标，该指标对桥墩的墩顶位移提出了更加严格的限制，进而能够指导设计。
[Abstract]:The nonlinear characteristics of pile members and foundation soil have an important effect on the seismic performance of bridges. The research on seismic behavior of bridges under soil-structure interaction is a hot topic in the field of bridge aseismic at present. In this paper, according to the characteristics of railway bridges, a combination of theoretical analysis and numerical simulation is used. The nonlinear behavior of pile foundation pier considering soil-structure interaction is studied systematically. The seismic performance evaluation method of pile foundation pier considering soil-structure interaction is studied. The main research contents are as follows:. (1) on the basis of in-depth study of various existing static push down models, combining with the characteristics of pile-soil interaction, A nonlinear static push-down model considering pile-soil interaction is proposed, which can consider the nonlinearity of pile members and foundation soil at the same time, and can well simulate the interaction between structure and soil under earthquake. Based on the static nonlinear calculation model of pile group foundation proposed in this paper, the influence of pile foundation longitudinal reinforcement ratio, hoop ratio, soil parameters, pier height and different loading modes on the bearing capacity and deformation capacity of pile foundation pier are studied. The development process and distribution characteristics of plastic hinge of pile body are summarized. In this paper, the reduction of demand spectrum considering pile-soil interaction is studied. Considering the characteristics of pile-soil interaction, the existing reduction methods of demand spectrum are compared. The results show that the Vidic reduction model and the Lu Xilin reduction model are more suitable for the reduction of the demand spectrum under the consideration of pile-soil interaction. 4) on the basis of comparative study of capability spectrum method, modified ability spectrum method, displacement coefficient method and performance point locus method proposed in ATC-40, a method for solving performance points is proposed by referring to the research results of [65]. The error between the method and the performance point locus method is less than 6%. 5) based on the study of various codes and references at home and abroad, and combined with the obvious increase of pier top displacement under pile-soil interaction, an evaluation index of bridge seismic performance is put forward, in which the displacement angle of pier top is taken as damage index. This index puts forward more strict limits on the pier top displacement and can guide the design.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U442.55

【参考文献】