盾构隧道衬砌结构受力分析的梁-弹簧系统模型

Study on Two Beam-spring Models for the Numerical Analysis of Segments in Shield Tunnel

盾构隧道衬砌结构由若干管片及其间的连接螺栓组成。在其断面受力的工程设计中，目前普遍采用梁-弹簧系统模型来模拟其受力性态。其中，梁可分成直梁和曲梁两类。本文在考虑弹簧刚度的轴向、切向和转动效应的同时，从卡氏（Castigliano）第二定理出发，给出了梁-弹簧模型的矩阵式，并论证了直梁-弹簧模型与曲梁-弹簧模型的一致性关系。在数值模拟计算过程中，还考虑了地层反作用力非线性情形和管片接头转动刚度正、负弯矩时的非对称性问题。

The lining structure of shield tunnel is composed of several segments and joints. In the design of the cross-section forces subjected to a definite external loading, beam-spring model is usually employed, in which beams are simulated as straight beam or curved beam. Based on the second Castigliano,s theorem, this paper will demonstrate .the consistent relation of the straight beam-spring model and the curved beam-spring model theoretically for linearly elastic body, and further give some examples to examine the two models numerically. In the meantime, the non-linear behavior of ground reaction to the structure and the asymmetrical characteristic of rotation stiffness specified to segment joints are simulated effectively.