从随机节理分布角度探讨工程岩体不均匀性和尺寸效应  

Discussion on the inhomogeneity and size effect of engineering rock mass from the perspective of random joints distribution

作　　者：吴顺川 张思瑞 韩龙强 侯英 李卓卿 WU Shunchuan;ZHANG Sirui;HAN Longqiang;HOU Ying;LI Zhuoqing(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming,Yunnan 65oo93,China;Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area,Ministry of Natural Resources of the People's Republic of China,Kunming,Yunnan 650093,China;Yunnan Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area,Kunming,Yunnan 650093,China;Baowu Resources Co.,Ltd.,Shanghai 200126,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]自然资源部高原山地地质灾害预报预警与生态保护修复重点实验室,云南昆明650093 [3]云南省高原山地地质灾害预报预警与生态保护修复重点实验室,云南昆明650093 [4]宝武资源有限公司,上海200126

出　　处：《中国矿业大学学报》2024年第6期1063-1073,共11页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(52334004,42302313);中国博士后科学基金项目(2023T160283)。

摘　　要：为研究随机节理分布对工程岩体不均匀性和尺寸效应的影响,采用等效岩体技术构建了156个含有不同随机节理的多尺度等效岩体模型.通过单轴压缩试验,研究不同岩体模型裂纹扩展机制,分析各模型力学参数随选取位置和纵向尺寸的变化.研究表明:岩体起裂位置多位于节理相交处,岩体发生明显宏观裂纹时,通常沿节理进行贯通.节理的随机分布使得工程岩体具有较强的不均匀性和尺寸效应,所含节理密度越小,岩体不均匀性越明显;首次提出用相对均匀尺度(RUD)来表征岩体是否达到相对均匀,一般情况下单轴抗压强度与弹性模量参数对应的RUD相同;但节理数较少时,弹性模量对应的RUD更大,说明节理的存在对岩体变形特性的影响更大.RUD和岩体表征单元体(REV)显著相关,大多数情况下,RUD和REV具有相同取值,即岩体的相对均匀尺度与表征单元体具有同等工程意义.In order to study the influence of the distribution of random joints on the inhomogeneity and size effect of the engineering rock mass,156 multi-scale equivalent rock mass models containing different random joints were constructed using the equivalent rock mass technique.Through the uniaxial compression test,the crack propagation mechanism of different rock mass models was studied,and the mechanical parameters of each model variation with the selected position and longitudinal size were analyzed.The results show that the initiation cracking position of rock mass is mostly located at the intersection of joints.When obvious macroscopic cracks occur in rock mass,they usually penetrate along the joints.The distribution of random joints makes the engineering rock mass show a strong inhomogeneity and size effect.The smaller the joint density,the more obvious the inhomogeneity of rock mass.Relative uniform dimension(RUD)is proposed to characterize whether the rock mass is relatively uniform.In general,the RUD corresponding to the uniaxial compressive strength and elastic modulus parameters are the same.However,when the number of joints is small,the RUD corresponding to the elastic modulus is larger,and the existence of joints has a greater impact on the deformation characteristics of rock mass.The RUD is significantly correlated with the representative elementary volume(REV).In most cases,RUD and REV have the same value,the RUD of the rock mass has the same engineering significance as the REV.

关 键 词：工程岩体 等效岩体技术 节理 尺寸效应 不均匀性 相对均匀尺度 

分 类 号：TU452[建筑科学—岩土工程]