Influence of volume compression on the unloading deformation behavior of red sandstone under damage-controlled cyclic triaxial loading

• DOI: 10.1016/j.jrmge.2022.09.009
• Publication Date: 2022-10-18T17:43:05Z
• Authors: Huaizhong Liu; Jianliang Pei; Jianfeng Liu; Mingli Xiao; Li Zhuo; Hongqiang Xie
• Keywords: Red sandstone; Lateral strain; Tangent modulus; Deformation mechanism

A reasonable evaluation of unloading deformation characteristics is great significance for the effective analysis and stability surrounding rocks after underground excavation. In this study, damage-controlled cyclic triaxial loading tests were conducted to investigate pore compaction mechanism its influences on behavior red sandstone, including Young's modulus, Poisson's ratio, volumetric strain, irreversible strain. The experimental results show that increases strains can be attributed mechanism, which almost dominates entire pre-peak process. consists reversible linear nonlinear strains, strain under influence porous grain structure. modulus tends increase then decrease due However, it hardly changes with increasing Instead, initial tangent highly related clearly reflects state sandstone. Furthermore, both deformations are independent confining pressure. This study beneficial theoretical modeling prediction