考虑衬砌接头的土—盾构隧道有限元模型初探

Study of finite element model of soil-shield tunnel taking account of segment joints of lining

本文作者详细推导了由梁单元和衬砌接头单元组成的混合单元的刚度矩阵 ,形成了考虑衬砌接头的土—盾构隧道有限元模型。利用有限元法计算了考虑衬砌接头和不考虑衬砌接头两种情况下衬砌的内力和衬砌的变形。由计算可知 ,衬砌接头对衬砌的轴力和位移影响相对较小 ,但对衬砌的弯矩影响较大 ,因此在盾构隧道的抗震设计中必须考虑衬砌接头的影响 ,否则将使设计趋于保守。

The stiffness matrix of mixed element is deduced in detail which consists of beam element and segment joints element of lining.Based on this kind of special element,finite element model of soil shield tunnel taking account of segment joints of lining can be established.Finite Element Method is used to calculate the maximum bending moment and axial force of lining and its deformation.The results show that the influence of segment joints to axial force and deformation of lining is slight,but to bending moment of lining is remarkable.Therefore,in the seismic design of shield tunnel,the influence of segment joints must be take into account,if not,the design will be reserved.