Identification and Prediction of Deformation Behavior Around a Shallow NATM Tunnel Using Strain Softening Model

摘要

In urban area, constructions of soft ground tunnels are associated with deformation of the ground andrnsurface subsidence. In this paper, a finite element analysis procedure considering strain softeningrnbehavior is applied for identification and prediction of deformational behavior around a shallowrnNATM tunnel. The method used here incorporates reduction of shear stiffness, as well as strainrnsoftening effects of given material strength parameters. The predictive capability of the method wasrnalso tested at three different stages in which higher accuracy of prediction was achieved accordingly inrnlatter stages. Deformation mechanism was also identified using reasonably tunnel parameters.