复杂艰险构造区铁路桥梁系统地震响应分析Part Ⅱ:SSI(土-结构相互作用)影响  

Seismic Response of Railway Bridges in Active Complex Tectonic Zones Part Ⅱ: Effects of SSI(Soil-Structure Interaction)

作　　者：陈令坤[1,2] 翟晨程 王璐 陈雯昕 朱利明 王尧周 张清华 张楠[5] 李乔[2] Chen Lingkun;Zhai Chencheng;Wang Lu;Chen Wenxin;Zhu Liming;Wang Yaozhou;Zhang Qinghua;Zhang Nan;Li Qiao(College of Architectural Science and Engineering,Yangzhou University,Yangzhou 225127,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;College of Transportation Engineering,Nanjing Tech University,Nanjing 210009,China;SUTCG Railway Transportation Design Institute,Nanjing 210017,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]扬州大学建筑科学与工程学院,江苏扬州225127 [2]西南交通大学土木工程学院,四川成都610031 [3]南京工业大学交通运输工程学院,江苏南京210009 [4]苏交科集团轨道交通设计院,江苏南京210017 [5]北京交通大学土木建筑工程学院,北京100044

出　　处：《地球科学》2022年第3期880-892,共13页Earth Science

基　　金：国家重点研发计划“交通基础设施”重点专项(No.2021YFB2600600);2018年度江苏省建设系统科技项目——江苏省防灾减灾抗震“四新”技术专题研究(No.2018ZD039);高速铁路基础研究联合基金项目(No.U1934207);轨道交通安全教育部重点实验室2019年开放基金项目(No.2019JZZ01);湖南创新型省份建设专项经费资助项目(No.2019RS3009);国家自然科学基金项目(Nos.52178180,5177863,51878561,51778533);湖南创新型省份建设专项(No.2019RS3009);中南大学创新驱动项目(No.502501006)。

摘　　要：目前国家正在复杂艰险构造区修建和规划新的铁路,地震等极限环境耦合作用对铁路交通的影响受到越来越多的关注.本文提出一种列车-桥梁-土耦合系统的数值模型,引入车辆简化模型、桥梁结构非线性有限元模型和层状土半解析模型,采用纯时域求解方法.利用p-y曲线、t-z曲线和q-z曲线建立土-桩基非线性模型,采用双线性模型模拟桥墩及桩基础的滞回特性,计算不良地质体发育区铁路列车-桥梁-土耦合系统的弹塑性地震响应,分析SSI对桥梁弹塑性地震响应的影响.研究表明,列车-桥梁-土耦合系统的第一弯曲模态通常是临界模态,即梁的一个半波形状导致土桥系统固有频率降低.另外,对于横向地震响应来说,考虑SSI(土-结构相互作用)后,影响地震响应的频率成分会发生变化,除了频率会变小之外,频段也会变宽.考虑SSI之前,影响频段是1.8~2.0 Hz,考虑SSI之后变为1.2~2.0 Hz之间.对于梁跨中竖向加速度,从考虑SSI之前的4.576 Hz到考虑SSI之后的14.215 Hz,建议考虑SSI进行设计时候应考虑竖向高阶振型影响.When constructing new railways in challenging tectonic zones, the influence of harsh situations like earthquakes on train traffic is increasingly being considered. With a time-domain solution approach, a numerical model of the coupled trainbridge-soil system is provided. In the poor geological development area, the elastic-plastic seismic response of the railroad trainbridge-soil coupled system is calculated using the p-y, t-z, and q-z curves. This means that bending the beam half-wave form reduces the inherent frequency of the coupled train-bridge-soil system, which is discovered to be the initial bending mode. After taking into account soil-structure interaction(SSI), the frequency components impacting the seismic response vary, and the frequency range widens as well as decreasing. The affecting frequency range is 1.8-2.0 Hz before SSI and 1.2-2.0 Hz after SSI, respectively. To design SSI, it is advised that the influence of vertical higher order vibration pattern should be addressed,since it varies from 4.576 Hz to 14.215 Hz before and after SSI consideration.

关 键 词：土-结构相互作用 铁路桥梁 土-桩基非线性模型 傅里叶分析 地震响应 工程地质 

分 类 号：P642[天文地球—工程地质学]