Numerical study of soil-rock mixtures with 3D numerical manifold method: Generation of random aggregate structure and discretized model

As the main material composition of many large landslides in China and other countries, the soil-rock mixtures (SRMs) have attracted many researchers to investigate their mechanical and hydraulic characteristics in the past several decades. Although in-door and in-situ tests still play the dominant role in obtaining the material parameters of SRMs, numerical methods are seen as a better choice regarding economy and practicality. As a competitive numerical method, the numerical manifold method (NMM), which can solve continuous and discontinuous problems in a unified framework, is used in the present work to investigate the hydraulic characters of SRMs. Before investigating the hydraulic characters of SRMs with NMM, the aggregate structural model and discretized model of SRMs should be built. To effectively build the aggregate structure model of SRMs with high rock content, a simplified random sequential addition method, which is based on E(A, B) concept and background mesh, is firstly developed. Then, the recently proposed parallel preprocessing strategy of NMM is used to generate the discretized model of SRMs. Finally, an illustrative example regarding the determination of effective permeability coefficient of SRMs is solved with 3DNMM. The proposed numerical model in investigating SRMs deserves further investigation.