泥炭质软土地区盾构隧道抗震性能研究

Study on Seismic Resistance for Shield Tunnel of Peat Soft Soil Area

文章采用ANSYS有限元分析软件,对土体与衬砌管片组成的耦合系统进行盾构隧道抗震三维有限元分析,其中考虑了土层的内摩擦角、内粘聚力。对不利于抗震的泥炭质土层采用多线性随动强化处理,使计算结果更加真实可靠。管片采用实体梁单元模拟,地震波选取汶川地震的地震动曲线。计算结果包括隧道周围土体的时程位移曲线、管片的轴力、剪力、弯矩等。最后从地震对盾构隧道的影响,对隧道抗震性能进行了初步评估,其结论可供昆明地区盾构隧道抗震设计参考。

The paper uses finite element analysis software ANSYS to conduct 3D finite element analysis on shield tunnel seismic coupling system composed of soil and lining segment, which takes into account the soil internal friction angle and cohesion force. To solve the problem of the seismic unfavorable peat soil, it uses multi-linear kinematic hardening treatment, and the result is more reliable and true. Segment uses solid beam element for simulation, and vibration curve selects the earthquake waves from Wenchuan Earthquake. The calculated results include the surrounding soil displacement curve, the axial force, shear and bending moment of the segment. With the study of earthquake impact on the shield tunnel, a preliminary evaluation has been carried out on the tunnel seismic resistance performance and behaviors. The paper makes conclusions which can be the reference for the seismic resistance design of shield tunnel in Kunming region.