受隧道和围岩的约束影响,水下隧道竖井在地震作用下的内力和变形特征与一般井筒式基础存在明显不同。基于黏弹性人工边界条件,采用通用有限元程序ANSYS建立了一种可以同时考虑土水介质与结构动力相互作用的有限元分析模型。通过对软土和岩质地基中竖井结构的横向地震响应进行分析。计算结果表明:不同土质条件下的竖井结构内力和变形规律基本一致,但受影响程度存在较大差异,主要反映在与隧道接头位置。上述结论可为进一步研究水下隧道竖井结构振动理论及竖井结构设计提供参考。
Influenced by the constraints of tunnel and surrounding rock,the internal force and deformation characteristics between underwater tunnel shaft and general shaft-type foundation are obviously different under the action of earthquake. Based on viscoelastic artificial boundary condition,a finite element analytical model is proposed using the general finite element program ANSYS considering the dynamic interaction between geological media and structure. The transverse seismic response of the shaft structure is analyzed for different geological conditions of surrounding rock,and the calculation results show that: the internal force and deformation of the shaft structure are basically identical under different geological properties,but show of significant difference in the extent of influence of factors,mainly reflected in the joint position of tunnel and shaft. The above conclusions provide the references for further research of vibration theory of underwater tunnel shaft as well as structure design.