盾构隧道管片接头接触特性的模拟分析

Simulation analysis of contact characteristics of the shield tunnel segment joints

以北京地铁四号线和武汉长江隧道工程为例,对其隧道管片接头接触特性进行精细三维有限元数值模拟,研究了隧道管片及其接头的应力应变分布,管片接头部分的接触状态、接触压力、接缝张开量.研究表明:隧道管片最大应变位置集中在管片螺栓手孔位置和接头受压区.随着接缝张开量的逐渐增大,接头部分由全断面接触状态变化到存在较大接缝张开量状态的过程中,接触应力分布线由以螺栓孔为中心的圆弧线逐渐变化到平直状态,最大应力值逐渐变大.计算结果表明:北京地铁与武汉长江隧道管片接头的张开比例分别达到50%和75%,研究成果为混凝土管片接头个性化设计提供依据.

Taking the projects of Beijing Subway Line 4 and the Wuhan Yangtze River Tunnel as the example, the three-dimensional finite element numerical simulation of the contact characteristics of the tunnel segment joints was carried out. The stress and strain distribution on the tunnel segment and its joints, the contact state of the segment joints, the contact pressure and the amount of joint open were studied. The research shows that the maximum strain location on tunnel segment concentrates on the location of the bolt hole and the compression zone of the joint. As the amount of seam increases,the joint part changes from the full contact state to larger seam state, the contact stress distribution line gradually changes from the arc line centered on the bolt hole to the straight state, and the maximum stress value gradually increases. The calculation results show that the open ratio of the segment joints of the Beijing Subway and the Wuhan Yangtze River Tunnel reaches 50% and 75%respectively. The research results provide the basis for the personalized design of the concrete joints.