超长沉管隧道地震响应快速分析方法研究  

Research on the Rapid Calculating Method of Seismic Analysis of Extra Long Immersed Tunnel

作　　者：李贞新[1] 徐国平[1] 苏宗贤 

机构地区：[1]中交公路规划设计院有限公司,北京市100088 [2]港珠澳大桥管理局,珠海市519015

出　　处：《公路》2015年第4期14-21,共8页Highway

基　　金：国家科技支撑计划课题;项目编号2011BAG07B01

摘　　要：在分析一般隧道结构与沉管隧道的不同点及动力响应差异基础上,明确了沉管隧道地震响应能否准确模拟主要取决于管节接头和节段接头的非线性、地基刚度计算及边界条件处理等;在此基础上建立了超长沉管隧道地震响应快速分析方法,关键点包括基于地震水准的地基刚度计算方法、管节接头剪力键及止水带受力及变形特性计算方法、节段接头剪力键及止水带受力及变形特性计算方法、初始水压力及止水带橡胶松弛影响考虑方法等;然后,基于超长沉管隧道地震响应快速分析方法,对港珠澳大桥超长沉管隧道进行了升温及降温工况下沉管隧道地震响应分析,明确了最不利位置为隧道斜坡段,指出了两侧GINA止水带地震变形量和剪力键剪力为抗震薄弱位置,揭示了节段式沉管隧道温度敏感性。课题研究建立的超长沉管隧道地震响应快速分析方法,能够实现沉管隧道设计与计算的互动,便于工程应用。Firstly, the difference of the immersed tunnel and ordinary tunnel structure are analyzed. In order to simulate the seismic response of immersed tunnel correctly, several aspects should be considered, which include nonlinear characteristics of the element joint and segment joint, soil stiffness, boundary conditions and the loads, etc. Then a rapid calculating method of seismic analysis of super longest immersed tunnel is proposed, in which the calculating method of soil stiffness in the three directions based on the earthquake level, stress and deformation behaviors for both the shear keys and watertight belts of elemental and segment joints are brought out. Effects of initial water pressure and plastic relaxation are also well considered in the method. Based on this method, seismic response analyses of the immersed tunnel for Hong Kong-Zhuhai-Macao Bridge （HZMB） are imp!emented under the two extreme temperature conditions, summer and winter. Results show that the slope segments are the most critical sections along the tunnel, and the deformation of GINA and shear forces of shear keys are the critical issues. Furthermore, the sensitive effect of temperature on the segmental immersed tunnel is also addressed and revealed. Furthermore, the proposed method, rapid design method for seismic analysis of ultra-long immersed tunnel, is of benefit to the connection between design and simulation of the immersed tunnel, and thus convenient to the practical application.

关 键 词：沉管隧道 地基动刚度 快速分析方法 管节接头 节段接头 剪力键 基础处理方案 

分 类 号：U452.28[建筑科学—桥梁与隧道工程]