GEOMETRIC NONLINEARITY ANALYSIS OF GROUNDSURFACE SETTLEMENT CAUSED BY TUNNELLING
隧道施工引起地面沉陷的几何非线性分析

The nominear finite element method based on the theory of Ducan-Chang model andgeometric nonlinedrity are first used to analyse the grouiidsurface settlement caused byNATM in shallow buried tunnel and the corresponding FEM program is developed.Themain characters of the method are using the theory of finite deformation to describe themovement of surrounding ground in shallow buried tunnel under excavation and usingDucan-Chang model to imitate the nonlinear property of ground;Thus,both the materialand movement properties of surrounding ground of tunnel are well described and the analysis of underground engineering is advanced a step.