岩石准静态条件下加载过程中的非平衡效应  

Non-equilibrium effect of rock under quasi-static loading condition

作　　者：王新宇[1] 邵珠山[1] 宋林[1,2] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]中国中铁一局集团有限公司,陕西西安710054

出　　处：《岩石力学与工程学报》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)~~

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.

关 键 词：岩石力学 滞弹细观单元 改进PM空间 非平衡效应 

分 类 号：TU45[建筑科学—岩土工程]