Test Study on Mechanical Properties of Mixture Mass of Loess and Crushed Rocks

摘要

Based on large-scale triaxial tests, the mechanical properties of loess and crushed rocks mixture mass of a freeway tunnel's surrounding rocks in Hebei were studied under the consideration of crushed rock's contents. The test results indicate that with the increase of crushed rocks contents, initial slope of deviatoric stress and axial strain curve increases at the same confining pressure. And corresponding axial strain decreases at the maximum partial stress value. At the same time, the mixture mass shows the characteristics of crisping deformation. Additionally, with the increase of crushed rocks contents, the internal frictional angle increases but the corresponding cohesion decreases. Therefore, the mechanical constitutive relationship of loses and crushed rocks mixture mass was simulated with double yield surface model. The method for determining the model parameters of this model was put forward at the same time.