摘要
岩石具有重要的不可忽略的黏滞特性,准静态条件下试样应力–应变曲线表现出明显的加载速率相关特性,宏观表现为试样加卸载过程中的弹性后效,弹性蠕变和松弛等非平衡态非线性效应。基于经典的PreisachMayergoyz空间理论模型,引入具有时间依赖性的滞弹细观单元,得到改进的PM空间理论模型。采用所提出的改进的PM空间模型,研究不同加载速率下试样应力–应变曲线关系特征,以及准静态条件下试样加载过程中的非平衡效应。最后,提出滞弹细观单元变形–时间曲线的试验获取方法以及改进PM空间的重构方式。研究结果表明,加载速率越小,试样滞回曲线所围成的面积越小;加载速率越大,试样达到平衡状态所需要的时间越长。
Rocks possess viscosity property, which cannot be ignored. Deformation behaviors of rock-like materials display the characteristics of the rate-dependence, which manifest macroscopically non-equilibrium nonlinear effect of elastic aftereffect, creep, and relaxation. Based on the classic Preisach-Mayergoyz space theoretical model, anelastic mesoscopic unit（AMU） possessing time-dependent peculiarity is introduced to obtain the modified PM theoretical model. By adopting the modified PM space model, characteristic of stress-strain curves with different loading rates and the non-equilibrium effect are studied in detail. Finally, experimental approach to obtain the deformation-time curve of the AMU and reconfiguration of the modified PM space is proposed. Results obtained in this paper indicate that, the area of stress-strain hysteresis loop increases with increment of loading rate. The larger the loading rate, the longer the time is taken for the sample to reach equilibrium state.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2016年第A01期2749-2757,共9页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51375373)
陕西省科技统筹创新工程计划项目(2013KTCQ01–16)~~
关键词
岩石力学
滞弹细观单元
改进PM空间
非平衡效应
rock mechanics
anelastic mesoscopic unit
modified PM space
non-equilibrium effect
