层状碎裂结构边坡灾变过程的离散元数值分析  

Distinct Element Analysis on catastrophic process of slope with layered cataclastic structure

作　　者：陈贺 解纹 余相贵 尹淏 秦雨樵 CHEN He;XIE Wen;YU Xianggui;YIN Hao;QIN Yuqiao(Yunnan Communications Investment&Construction Group Co.,Ltd.,Kunming,Yunnan 650103,China;Broadvision Engineering Consultants Co.,Ltd.,Kunming,Yunnan 650041,China;Yunnan Key Laboratory of Digital Communications,Kunming,Yunnan 650000,China;Yunling Construction Co.,Ltd.,Yunnan Communications Investment&Construction Group,Kunming,Yunnan 650000,China;Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China)

机构地区：[1]云南省交通投资建设集团有限公司,云南昆明650103 [2]云南省交通规划设计研究院股份有限公司,云南昆明650041 [3]云南省数字交通重点实验室,云南昆明650000 [4]云南交投集团云岭建设有限公司,云南昆明650000 [5]中国科学院武汉岩土力学研究所,湖北武汉430071

出　　处：《公路交通科技》2025年第3期115-125,164,共12页Journal of Highway and Transportation Research and Development

基　　金：国家重点研发计划项目(2022YFC3002602)。

摘　　要：【目标】利用离散单元法探讨层状碎裂结构边坡灾变过程。【方法】基于微细观缺陷服从Weibull概率分布的统计结果,提出了可表征非均匀性的岩体模型,通过顺倾和反倾节理面切割均质边坡建立了顺倾层和反倾层碎裂结构边坡模型。开展了系列均质度条件下离散单元法单轴压缩试验,完成了10余组不同节理面摩擦系数、节理面间距、边坡倾角条件下边坡变形破坏过程数值模拟。从胶结破坏数、速度、动能等方面分析了顺倾层和反倾层边坡灾变过程特征,并将破坏模式与室内模型试验结果进行了对比分析。【结果】随着均质度增大,单轴压缩强度和脆性指数分别先增大和减小,而当均质度达到7之后近乎不变;节理面越光滑、节理面间距越小,边坡越陡,裂隙延伸扩展越多,破坏范围越大;相比节理面间距和摩擦系数,边坡倾角对最大速度的影响更为显著;顺倾层边坡的灾变过程为中上部岩体变形—剪切带由坡顶至坡脚扩展—抗滑段剪断—圆弧滑动,而反倾层边坡的灾变过程为中部临空面岩体变形—中部开裂—裂隙向坡脚扩展—翻折倾倒,坡顶岩体后缘开裂—翻折倾倒—坡面滑动。【结论】非均匀性岩体模型解决了采用岩石胶结模型模拟岩石时遇到的峰后应力陡降缺陷,研究结果与多个室内模型试验相吻合,验证了离散单元法数值计算模型和计算方法的合理性和可靠性。[Objective]The failure process of slope with layered cataclastic structure was investigated by using the discrete element method.[Method]The rock mass model,characterizing the inhomogeneity,was proposed based on the statistical results of micro-defects obeying Weibull probability distribution.The homogeneous slopes were cut according to bedding and counter-tilt joint surfaces respectively.The cataclastic structured bedding slope and counter-tilt slope models were established.A series of distinct element uniaxial compressive tests were carried out with different heterogeneity indicators.The slope deformation failure processes were numerically simulated on more than 10 slope models configured with different joint surface friction coefficients,joint surface spaces,and slope angles.The catastrophic process features of bedding slope and counter-tilt slope were analyzed from the aspects of bond failure number,velocity,kinetic energy,etc.The failure modes were compared with the result from laboratory tests.[Result]With the increase of homogeneity,the uniaxial compressive strength and brittleness indexes increase and then decrease respectively,which remain almost unchanged when the homogeneity reaches 7.The smoother the joint surface,the smaller the joint surface space,and the steeper the slope.The more the cracks extend and expand,and the greater the failure range.The slope angle affects the maximum velocity more significantly than joint friction coefficient and joint space.The sequence of bedding slope catastrophic process is upper and middle rock mass deformation,shear band propagating from slope top to foot,anti-slip segment shearing,and arc-shaped sliding.Whereas the sequence of counter-tilt slope is rock mass deformation at middle boundary surface of free space,cracking in middle,crack propagating towards slope foot,folding and toppling,cracking at rear edge of slope top,folding and toppling,sliding along slope surface.[Conclusion]The non-homogeneity rock mass model solves the problem of post-peak stress drop encou

关 键 词：道路工程 边坡灾变过程 离散单元法 层状碎裂边坡 均质度 

分 类 号：U416.1[交通运输工程—道路与铁道工程]