岩质反倾边坡复合倾倒破坏分析
2020-02-16孙朝燚陈从新郑允张伟马力张海娜张亚鹏
孙朝燚 陈从新 郑允 张伟 马力 张海娜 张亚鹏



摘 要:針对岩质反倾边坡滑动倾倒复合破坏的研究不足,首先建立了边坡滑动-块状倾倒-弯曲倾倒复合破坏的地质模型,具体可分为滑动区、块状倾倒区和弯曲倾倒区;然后根据三个分区岩块的破坏机制,提出了各个分区的力学模型;并基于极限平衡理论和悬臂梁模型,提出了边坡滑动-块状倾倒-弯曲倾倒复合破坏的逐步分析方法;最后通过一个工程实例验证了所提地质模型和分析方法的正确性. 研究结果表1明:岩质反倾边坡滑动-块状倾倒-弯曲倾倒复合破坏的稳定性由滑动-块状倾倒复合破坏区域控制;块状倾倒区域属于主动破坏区域,滑动区属于被动破坏区域,治理加固时应重点加固块状倾倒破坏区.
关键词:岩质反倾边坡;横向节理;边坡稳定性;数值模拟;分析方法
中图分类号:P642 文献标志码:A
Analysis of Anti-dip Rock Slopes Against Composite Toppling Failure
SUN Chaoyi1,2,CHEN Congxin1,ZHENG Yun1?,ZHANG Wei1,
MA Li1,ZHANG Haina1,2,ZHANG Yapeng1,2
(1. State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute
of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;
2. University of Chinese Academy of Sciences,Beijing 100049,China)
Abstract:Aiming at the insufficient research on the complex sliding-toppling failure of anti-dip rock slopes,the geological model of complex sliding-block-flexural toppling failure was constructed,firstly,which contains the sliding,block toppling and flexural toppling zones. Next,based on the failure mechanisms of these three zones,their mechanical models were established,respectively. Then,the stability analysis approach of the complex sliding-block-flexural toppling failure was proposed according to the limit equilibrium theory and the cantilever beam model. Finally,one case study was performed for practical verification on the proposed geomechanics models and analysis approach. The results show that the stability of the complex sliding-block-flexural toppling zones is controlled by the block-flexural toppling zones. Further,the block and flexural toppling zones are active and passive failure zones,respectively. Consequently,the block toppling zone plays a vital role in slope design treatment.
Key words:anti-dip rock slopes;transverse joints;slope stability;numerical simulation;analysis approach
孙朝燚等:岩质反倾边坡复合倾倒破坏分析
倾倒破坏是岩质反倾边坡的主要失稳模式之一,常见于露天采矿、水利水电、公路铁路等各类工程边坡中,这些边坡的失稳给工程建设和人民生活造成了严重的危害[1-6]. Goodman和Bray[7]从单个岩层破坏的力学机制出发,将倾倒破坏分为弯曲倾倒、块状倾倒和块状-弯曲复合倾倒三种类型. 若岩质边坡中存在一组与边坡走向近似、插入坡内的主控裂隙组如层理、页理等,边坡类似叠合悬臂梁,由于重力作用,岩块承受着拉伸和压缩弯曲应力,当每个岩……
