关键词: 初始各向异性, 格构模型, 离散单元法, 宏微观关联

Abstract: The initial anisotropy resulting from particle shape and granular arrangement significantly influences the mechanical behaviors of cemented geo-materials. To establish an anisotropic strength criterion for cemented geo-materials that incorporates micromechanical mechanisms, we utilize regularly arranged elliptical particle assemblies. By employing a micro-analytical model, we develop an equivalent lattice model for these assemblies, assign particle contact properties to the corresponding lattice beams, and apply a size-dependent nonlinear yield criterion to describe beam breakages. Through mechanical analysis of the instability state of the representative volume element, we propose macroscopic strength and corresponding strength parameters expressed in terms of microscopic parameters (particle shape parameters, contact parameters) and the tilting angle. The correctness of the analytical solution is verified through numerical simulations based on the discrete element method. The results demonstrate that the proposed strength analytical formula can effectively reflect the influence of initial anisotropy on the mechanical properties of cemented geo-materials. The macro-micro quantitative correlation analytical solution reveals the quantitative influence of initial anisotropy caused by particle shape and regular arrangement, as well as inter-particle contact characteristics, on macroscopic mechanical behaviors.

Key words: inherent anisotropy, lattice mode, discrete element method, micro–macro relation