运营地铁隧道收敛变形对接头性能影响的研究

Research on Joints Properties for Tunnel Convergence Deformation of Operating Metro

基于上海运营地铁8号线某区间隧道横向收敛变形的实测数据,建立了隧道横、竖向变形量之间的相互关系.根据该关系式采用四点加载的方法,通过数值模拟对隧道纵向接缝张开情况及螺栓受力情况进行了研究.研究结果表明:当隧道呈"横鸭蛋"变形时,隧道在封顶块接缝处产生内张角,而在其它接缝处产生外张角,且外张角远小于内张角.当隧道横向变形量△a=15 mm时,封顶块接缝处的螺栓开始产生屈服.管片接缝处的接缝张开值与横向变形量△a近似呈线性变化,且封顶块接缝处的张开值并未受到螺栓屈服的影响.当封顶块处接缝张开值约为3 mm时,连接螺栓开始屈服,且隧道纵缝间螺栓预紧力的大小对管片各接缝张开值的影响较小.

Based on tunnel convergence deformation＇ s measured data of metro line 8 in Shanghai, the relation- ship between vertical deformation and horizontal deformation is established. By imposing displacement boundary （four- point loading method）, the finite element software is applied to calculate the longitudinal joints＇ opening and the connecting bolts＇ stress state. The results show that when the deformation of tunnel looks like ＂horizontal egg＂, joints between the capping block and the adjacent block open inward, the joints in other positions open outward, and the joints opening value inward is larger than the outwards. When tunnel＇ s horizontal deformation Aa is equal to 15mm, the connecting bolts begin to yield. The relationship between the joints＇ opening value and the tunnel＇ s horizontal deformation is linear. The connecting bolts＇ yield has no effect on the joints＇ open- ing value. When the joints opening value is equal to 3mm in the capping block, the connecting bolt begins to yield and the value of bolts＇ preload has little effect on the joints＇ opening value.