Abstract:

An analytical solution on the relationship of axial force, moment and rotation of segment joints is employed in a proposed iterative algorithm for mechanical analysis of segment lining of shield tunnel, in which the nonlinear characteristic of bending stiffness of segment joints is fully considered. Under the background of Nanjing Weisanlu Yangtze River tunnel, the influence of bending stiffness of segment joints for the numerical solution of segment lining is analyzed. The mechanical behavior of segment ling in typical composite strata is also studied. Conclusions drawn are as follows: The proposed method is very convenient, the moment distribution of segment lining in composite strata is much different from that in the uniform strata. The composite strata increases the nonuniform distribution of moment in segment lining and may lead to remarkable increase of segment moment. Therefore the distribution of the actual strata should be considered in the design calculation. The proposed method and results of the analysis in this paper is valuable for the design of similar projects in practice.

Key words: shield tunnel, composite strata, segment lining, mechanical analysis