Transversely Isotropic Mechanical Properties And Constitutive Model Of Slate

The physical and mechanical properties of rocks such as metamorphic rocks and layered sedimentary rocks in nature are distinctly different in perpendicular to the direction of the bedding plane and parallel to the bedding plane,called rock isotropic.The layered rocks have transversely isotropic properties,and the layered rock mass is widely distributed in China.In the construction of rock engineering such as highway,railway and mine,the transversely isotropic of the rock has important influence on the stability of rock engineering.The study of rock isotropic is of great significance to the design,construction,deformation and stability prediction of rock engineering.In this paper,the transversely isotropic elastic,plastic and creep properties of carbonaceous slate are studied by experiments,and the corresponding constitutivemodel is proposed.In the aspect of elastoplasticity,we carried out the conventional triaxial compression test of horizontal bedding samples and vertical bedding samples,established the elasto-plastic constitutive model of transversely isotropic rock,proposed a method for model parameter and solved the model parameters.Taking the carbonaceous slate as an example,the proposed transversely isotropic elastoplastic model and the method of parameter solving are validated.The transversely isotropic strength characteristics of the rock are analyzed by using the proposed model.In terms of creep,we carried out the conventional triaxial compression test of horizontal bedding samples and vertical bedding samples,studied the creep characteristics of carbonaceous slate with different bedding in different loading paths,and analyzed the creep flow direction.We used the internal variable creep equation based on the irreversible strain,and established the creep constitutive model of the transversely isotropic rock.The model parameters are solved and the model parameters are solved,proposed a method for model parameter and solved the model parameters.Taking the carbonaceous slate as an example,the proposed transversely isotropic creep model and the method of parameter solving are validated.The results of this study will provide a theoretical basis for enriching the basic theory of rock mechanics and solving the related engineering problems.The numerical simulation of elastoplastic constitutive model of transversely isotropic rock is carried out,and the total rigid matrix of elastoplastic constitutive model of transversely isotropic rock is deduced.In the Fortran compilation environment,the sub-program UMAT of ABAQUS is used to develop the elasto-plastic constitutive model of transversely isotropic rock,and the UMAT subroutine is embedded in ABAQUS operation to simulate the conventional The results show that the transversely isotropic elastoplastic constitutive model and the correctness of the program are verified by the triaxial compression test.The model proposed in this paper is applied to the research of tunnel excavation with different bedding planes,analyzed the influence of the bedding angle on the tunnel deformation.Compared with the calculation results of the Hill model,the model proposed in this paper can better be applied to the transversely Homogeneous geomaterials.