Investigation of equivalent strength parameters of soil-rock mixture using numerical manifold method
Junfeng Li, Yongtao Yang, Yang Xia, Hong Zheng, Shuilin Wang
Abstract
As binary geological media, soil-rock mixtures (SRMs) exhibit a distinct gradational composition, leading to their unique mechanical behaviors. To appraise the stability of SRM slopes, it is essential to determine equivalent parameters of SRMs, which are typically obtained through experimental and numerical methods. In contrasted to other numerical methods, the numerical manifold method (NMM) is more effective in addressing SRM problems. This is because the high-precision regular mathematical meshes in NMM can be used without aligning with the soil-rock interfaces and boundaries of SRMs. In the current research, the equivalent strength parameters of SRMs, i.e. the equivalent cohesion and internal friction angle , are determined using NMM. Initially, an NMM triaxial numerical model is established and validated based on triaxial experiments. Subsequently, the soil and rock parameters are derived through parameter inversion. Moreover, the impacts of rock content, size, shape and rock blocks' major-axis orientation on and of SRMs are thoroughly examined using the NMM triaxial numerical model. Additionally, a fitting function is proposed to link to the rock content and size of SRMs. When other influencing factors are fixed, the above fitting model leads to the following conclusions: (1) the predicted of SRMs increase with the increase of rock content; and (2) SRM samples with smaller rocks display a higher predicted .