水动力-应力-化学溶蚀耦合作用下劣化灰岩能量演化规律与损伤本构模型  

Energy evolution and constitutive model for damage of degraded limestone under coupling effects of hydrodynamic-stress-chemical corrosion

作　　者：杨忠平[1,2,3] 侯善萌 张益铭 高宇豪 刘新荣[1,2,3] YANG Zhongping;HOU Shanmeng;ZHANG Yiming;GAO Yuhao;LIU Xinrong(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Key Laboratory of New Technology for Construction of Cities in Mountain Area of Ministry of Education,Chongqing 400045,China;National Joint Engineering Research Center of Geohazards Prevention in Reservoir Area,Chongqing 400045,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [3]重庆大学库区环境地质灾害防治国家地方联合工程研究中心,重庆400045

出　　处：《岩土工程学报》2025年第4期759-768,共10页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(42177125,41972266);国家重点研发计划课题(2021YFB3901402,2018YFC1504802)。

摘　　要：库水位常年周期性波动,导致消落带基岩处于水动力冲蚀的干湿循环状态,加之覆岩的自重作用,促使基岩强度的劣化。为研究水动力-应力-化学溶蚀耦合条件下岩体劣化规律,在现场调查基础上,开展了该耦合条件下灰岩试样劣化试验,阐明了此条件下灰岩能量演化规律并提出了损伤本构模型。结果表明:根据能率-位移曲线,将岩石破坏过程划分为易损区压密、微裂隙闭合、弹性变形、微裂隙扩展及峰后破坏5个阶段;随着劣化应力的增加,部分耗散能提前释放,耗散能与弹性能相等时的应变逐渐减小;随着干湿循环次数的增加,其破坏时总能量对应力的敏感性增强;揭示了水动力-应力-化学溶蚀耦合机理;提出了水动力-应力-化学溶蚀耦合作用下考虑压密阶段劣化灰岩的损伤本构模型,预测精度较高,可为库区灾害预测防治提供一定的理论指导。The reservoir water level undergoes annual cyclical fluctuations,which leads to the state of hydrodynamic erosion of wetting-drying cycles of the bedrock in the hydro-fluctuation belt.In addition,the self-weight of the overlying rock mass also reduces the strength of the bedrock.To study the deterioration law of the rock mass under the coupling of hydrodynamicstress-chemical corrosion,the degradation tests are conducted on limestone samples based on the field investigations.The law of energy evolution of limestone under the coupling of hydrodynamic-stress-chemical corrosion is elucidated,and the constitutive model for damage is proposed.The results show that according to the energy rate-strain curve,the rock failure process can be divided into five stages:compaction of vulnerable zone,microfracture closure,elastic deformation,microfracture extension,and post-peak failure.With the increase of the degradation stress,part of the dissipative energy is released in advance,and the strain at which the dissipated energy equals the elastic energy gradually decreases.The sensitivity of the total energy to the degradation stress increases with the increase of the wetting-drying cycles.The coupling mechanism of hydrodynamic-stress-chemical corrosion is revealed.The constitutive model for damage considering the deterioration of limestone at the compaction stage under the coupling of hydrodynamic-stress-chemical corrosion is proposed,which has higher prediction accuracy and can provide some theoretical guidance for disaster prediction and prevention in reservoir areas.

关 键 词：水动力-应力-化学溶蚀耦合 单轴压缩 能量演化 WEIBULL分布 本构模型 

分 类 号：TU43[建筑科学—岩土工程]