Part of #Estimation of Creep Deformations in Circular Tunnels Considering Elasto-Plastic Behavior# :
Publishing year : 2012
Conference : 7th International Conference on Science and Technology
Number of pages : 7
Abstract: By excavating an underground space, the state of stress and displacement in the environment are changed in comparison with initial state. As time passes, the variation of displacement mainly depends on the creep behavior of the hosting rock mass. In this paper, an elasto-viscoplastic creep model is proposed. In the proposed model, the main purpose is to consider plastic deformations increasing with time. The viscoplastic behavior of rocks plays a key role in tunneling works, especially for deep tunnels subjected to large in situ stresses. Using the nonlinear Hoek-Brown yield criterion in a creep model is another important objective of this paper, which eliminates the estimation of specific specific Mohr-Coulomb strength parameters from the Hoek-Brown parameters. The equations are related to the proposed model, and then, to achieve a numerical solution of the equations, the finite difference software (FLAC (2D) -FISH Editor) is used. The application of the proposed model is illustrated numerically using a finite difference software FLAC (2D).