暗挖隧道对近接电缆隧道影响的数值计算研究

Numerical Computational Study of the Impact of Concealed Tunnels on Proximity Cable Tunnels

针对地铁暗挖隧道施工对电缆隧道衬砌结构造成的裂损病害问题,运用有限差分软件模拟暗挖隧道正交下穿电缆隧道不同工况,提取并拟合电缆隧道的沉降值作为位移载荷,用ABAQUS有限元软件建立荷载-结构模型,将位移荷载加载到采用内聚力模型本构的衬砌结构上来模拟裂缝萌生与发展.得到结果如下:暗挖隧道正交下穿电缆隧道工况下,电缆隧道二次衬砌底板主要受到拉应力的影响最大,电缆隧道衬砌底板裂缝起裂、扩展时产生的最大应力与隧道之间的垂直距离(净距)、电缆隧道的断面尺寸有关;暗挖隧道正交下穿电缆隧道工况下,对电缆隧道产生的裂缝几何特征进行了分析,裂缝的宽度、长度、深度同电缆隧道断面尺寸、净距成线性关系.

For the crack damage problems caused by the subway tunnelling construction on the cable tunnel lining structure,the finite difference software is used to simulate the different working conditions of the cable tunnel orthogonal to the tunnelling tunnel.The settlement value of the cable tunnel is extracted and fitted as the displacement load,and the load-structure model is established by using the ABAQUS finite element software to load the displacement load onto the lining structure which adopts the Cohesive zone model to simulate the cracks sprouting and developing.Cohesive zone model lining structure to simulate the cracks sprouting and develop-ment.The results are as follows:Under the working condition of the cable tunnel,the secondary lining plate of the cable tunnel is mainly affected by the tensile stress,and the maximum stress generated by the crack initiation and expansion of the lining plate of the cable tunnel is related to the vertical distance between the tunnels and the cross-section size of the cable tunnel.The geometric characteristics of the cracks generated in the cable tunnel were analyzed under the condition of orthogonal underpassing of cable tunnel in the concealed tunnel,and the width,length and depth of the cracks were linearly related to the section size and clear distance of the cable tunnel.