Creep deformation and failure mechanisms in deep soft rock: A hybrid contact model analysis

作者：Qingwen Li, Lei Zhang, Wenxia Li, Chuangchuang Pan, Mengjiao Xu, S.B. Zhang, Kang Xu · 发表于：Physics of Fluids · 年份：2025 · DOI：10.1063/5.0271029 · 被引用次数：7 · 研究领域：Rock Mechanics and Modeling、Landslides and related hazards、Tunneling and Rock Mechanics

Deep soft rock has become a primary focus of research due to its susceptibility to creep deformation and failure under long-term geological stress. In this study, a new Burgers-parallel bond hybrid contact creep model is developed using the Particle Flow Code (PFC2D) program for secondary development. Based on this model, both conventional and creep mesoscopic tests of sandy mudstone under varying initial confining pressures are simulated. The results reveal significant differences in the full stress–strain and volume strain curves under different initial confining pressures and axial compression loading and confining pressure unloading ratios. As initial confining pressures and axial compression loading and confining pressure unloading ratios increase, the total creep duration and creep slope at all levels also increase. Under the creep stress path, the compressive bearing capacity will decrease. However, increasing initial confining pressures and reducing axial compression loading and confining pressure unloading ratios will delay the reduction in its compressive bearing capacity. By analyzing the evolution of microcracks and contact ratios in sandy mudstone, the internal mechanisms behind macroscopic deformation are revealed. The initial confining pressures significantly influences the contact ratio and the number of cracks under varying axial compression loading and confining pressure unloading ratios. The evolution of creep energy reflects the process of strength failure...