A comparative Study on the Analysis of Elastic Plastic and Viscoelastic Constitutive Model in Soft Rock large Deformation Tunnel

Abstract

With the construction of large highway engineering, large section soft rock highway tunnel is more and more. In the process of excavation, large section highway tunnel, soft surrounding rock and complex stress, during the excavation process prone to large deformation. Reasonable determination of the deformation of the large section soft rock highway tunnel is particularly important. According to the geological conditions and the mechanical characteristics of surrounding rock, using elastic-plastic and visco elastic constitutive model for deformation of the same level under different embedding rock by numerical analysis, the same rock using different constitutive relations, area difference, measured data through the laying on the site to provide the comparative analysis by the viscoelastic constitutive relation constitutive model is closer to the actual site, which is due to the large section soft rock tunnel has obvious time effect in the process of excavation, therefore in the process of excavation for large deformation of soft rock tunnel is more close to the actual rheological constitutive model considering the effect of amount.