狮子坪水电站二古溪倾倒边坡成因机制分析
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摘要
二古溪边坡位于四川省理县狮子坪水电站库区,2013年9月水库蓄水高度升至2 540m后,边坡出现强烈变形,致317国道阻断至今。初步分析边坡在河谷快速下切过程中,坡体内岩体应力释放产生向临空面的位移,由于存在软硬两种岩体,变形过程中产生了不协调变形,软岩的变形位移量大而硬岩较小,致使在硬岩中形成应力集中,当应力大于硬岩强度时,硬岩发生破坏。5.12汶川地震、公路开挖及降雨进一步加剧边坡的倾倒破坏,随后坡体逐步达到应力平衡。通过大量现场地质调查,并结合钻孔岩芯、变形监测对二古溪边坡倾倒变形成因进行研究,结果表明:二古溪倾倒边坡属于软硬岩互层的早期倾倒边坡,在地震作用下边坡岩体造成了损伤,蓄水与强降雨加剧了边坡的变形;目前边坡处于应力调整期,变形将会持续较长的一段时间,蓄水位升高无疑还将加剧其变形。
Erguxi toppling slope is located in the reservoir area of Shiziping hydropower station in Sichuan Province.On September 2013 the storage water level was raise up to 2 540 m and the slope deformed strongly and then blocked G317 road.Preliminary analysis shows that during the rapid cutting of valley,the stress release in rock mass leads to displacement towards the free face,and because of hard rock and soft rock,the deformation is uncoordinated.The deformation of soft rock is lager than that of hard rock,resulting in the stress concentration in hard rock,and when the stress is larger than the hard rock strength,hard rock failure happens.The 5.12 Wenchuan earthquake together with highway excavation and rainfall further exacerbated the toppling slope,and then the slope gradually reached a state of stress balance.According to field geological survey,we analyzed the formation mechanism of the toppling slope by means of drilling core and monitoring.Results reveal that the slope is in the early stage of toppling of interbedded soft and hard rocks.The damage of slope rock mass was caused by earthquake and was intensified by water storage and rainfall.At present the slope is in stress adjustment and the deformation will continue for a long period,and also water level rise will no doubt exacerbate its deformation.
Erguxi toppling slope is located in the reservoir area of Shiziping hydropower station in Sichuan Province.On September 2013 the storage water level was raise up to 2 540 m and the slope deformed strongly and then blocked G317 road.Preliminary analysis shows that during the rapid cutting of valley,the stress release in rock mass leads to displacement towards the free face,and because of hard rock and soft rock,the deformation is uncoordinated.The deformation of soft rock is lager than that of hard rock,resulting in the stress concentration in hard rock,and when the stress is larger than the hard rock strength,hard rock failure happens.The 5.12 Wenchuan earthquake together with highway excavation and rainfall further exacerbated the toppling slope,and then the slope gradually reached a state of stress balance.According to field geological survey,we analyzed the formation mechanism of the toppling slope by means of drilling core and monitoring.Results reveal that the slope is in the early stage of toppling of interbedded soft and hard rocks.The damage of slope rock mass was caused by earthquake and was intensified by water storage and rainfall.At present the slope is in stress adjustment and the deformation will continue for a long period,and also water level rise will no doubt exacerbate its deformation.
引文
[1]黄润秋.岩石高边坡的时效变形分析及其工程地质意义[J].工程地质学报,2000,8(2):148-153.(HUANG Run-qiu.Time-Dependent Deformation of a High Rock Slope and Its Engineering Geologic Significance[J].Journal of Engineering Geology,2000,8(2):148-153.(in Chinese))
[2]孙东亚,彭一江,王兴珍.DDA数值方法在岩质边坡倾倒破坏分析中的应用[J].岩石力学与工程学报,2002,21(1):39-42.(SUN Dong-ya,PENG Yi-jiang,WANG Xing-zhen.Application of DDA Method in Stability Analysis of Topple Rock Slope[J].Rock Mechanism and Engineering,2002,21(1):39-42.(in Chinese))
[3]芮勇琴,贺春宁,王惠勇.开挖引起大规模倾倒滑移边坡变形、破坏分析[J].长沙交通学院学报,2001,17(4):8-12.(RUI Yong-qin,HE Chun-ning,WANG Hui-yong.Analysis of Deformation and Failure Development of the Large-scale Toppling Slope under Mining[J].Journal of Changsha Jiaotong University,2001,17(4):8-12.(in Chinese))
[4]王建锋,TANG W H,崔政权.块状岩体边坡倾倒破坏稳定性分析[J].中国地质灾害与防治学报,2001,12(4):1-8.(WANG Jian-feng,TANG W H,CUI Zheng-quan.Stability Analysis of Toppling Failure of Block Rock Slopes[J].Chinese Journal of Geological Hazard and Control,2001,12(4):1-8.(in Chinese))
[5]汪小刚,贾志欣,陈祖煜,等.岩质边坡倾倒破坏的稳定分析方法[J].水力学报,1996,(3):7-15.(WANG Xiao-gang,JIA Zhi-xin,CHEN Zu-yu,et al.The Research of Stability Analysis of Toppling Failure of Jointed Rock Slopes[J].Journal of Hydraulic Engineering,1996,(3):7-15.(in Chinese))
[6]杨根兰,黄润秋,严明,等.小湾水电站饮水沟大规模倾倒破坏现象的工程地质研究[J].工程地质学报,2006,14(2):165-171.(YANG Gen-lan,HUANG Run-qiu,YAN Ming,et al.Engineering Geology of a Large-scale Toppling Deformation at Xiaowan Hydropower Station[J].Journal of Engineering Geology,2006,14(2):165-171.(in Chinese))
[7]赵小平,李渝生,陈孝兵,等.澜沧江某水电站右坝肩工程边坡倾倒变形问题的数值模拟研究[J].工程地质学报,2008,16(8):298-303.(ZHAO Xiao-ping,LI Yu-sheng,CHEN Xiao-bing,et al.Numerical Simulation for the Problem of Project Slope Toppling Deformation on the Right Abutment of a Hydropower Station Dam on Lancang River[J].Journal of Engineering Geology,2008,16(8):298-303.(in Chinese))
[8]陈孝兵,李渝生,赵小平.底摩擦重力试验在倾倒变形岩体稳定性研究中的应用[J].地学前缘,2008,15(2):300-304.(CHEN Xiao-bing,LI Yu-sheng,ZHAO Xiao-ping.The Application of Bottom Friction Gravity Test to the Study of the Toppling Rock Mass[J].Earth Science Frontiers,2008,15(2):300-304.(in Chinese))
[9]蔡国军,黄润秋,严明,等.反倾向边坡开挖变形破裂响应的物理模拟研究[J].岩石力学与工程学报,2008,27(4):812-817.(CAI Guo-jun,HUANG Run-qiu,YAN Ming,et al.Physical Simulation on Deformation and Failure Response of an Anti-inclined Slope during Excavation[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(4):812-817.(in Chinese))
[10]韩贝传,王思敬.边坡倾倒变形的形成机制与影响因素分析[J].工程地质学报,1999,7(3):213-217.(HAN Bei-chuan,WANG Si-jing.Mechanism for Toppling Deformation of Slope and Analysis of Influencing Factors on It[J].Journal of Engineering Geology,1999,7(3):213-217.(in Chinese))
[2]孙东亚,彭一江,王兴珍.DDA数值方法在岩质边坡倾倒破坏分析中的应用[J].岩石力学与工程学报,2002,21(1):39-42.(SUN Dong-ya,PENG Yi-jiang,WANG Xing-zhen.Application of DDA Method in Stability Analysis of Topple Rock Slope[J].Rock Mechanism and Engineering,2002,21(1):39-42.(in Chinese))
[3]芮勇琴,贺春宁,王惠勇.开挖引起大规模倾倒滑移边坡变形、破坏分析[J].长沙交通学院学报,2001,17(4):8-12.(RUI Yong-qin,HE Chun-ning,WANG Hui-yong.Analysis of Deformation and Failure Development of the Large-scale Toppling Slope under Mining[J].Journal of Changsha Jiaotong University,2001,17(4):8-12.(in Chinese))
[4]王建锋,TANG W H,崔政权.块状岩体边坡倾倒破坏稳定性分析[J].中国地质灾害与防治学报,2001,12(4):1-8.(WANG Jian-feng,TANG W H,CUI Zheng-quan.Stability Analysis of Toppling Failure of Block Rock Slopes[J].Chinese Journal of Geological Hazard and Control,2001,12(4):1-8.(in Chinese))
[5]汪小刚,贾志欣,陈祖煜,等.岩质边坡倾倒破坏的稳定分析方法[J].水力学报,1996,(3):7-15.(WANG Xiao-gang,JIA Zhi-xin,CHEN Zu-yu,et al.The Research of Stability Analysis of Toppling Failure of Jointed Rock Slopes[J].Journal of Hydraulic Engineering,1996,(3):7-15.(in Chinese))
[6]杨根兰,黄润秋,严明,等.小湾水电站饮水沟大规模倾倒破坏现象的工程地质研究[J].工程地质学报,2006,14(2):165-171.(YANG Gen-lan,HUANG Run-qiu,YAN Ming,et al.Engineering Geology of a Large-scale Toppling Deformation at Xiaowan Hydropower Station[J].Journal of Engineering Geology,2006,14(2):165-171.(in Chinese))
[7]赵小平,李渝生,陈孝兵,等.澜沧江某水电站右坝肩工程边坡倾倒变形问题的数值模拟研究[J].工程地质学报,2008,16(8):298-303.(ZHAO Xiao-ping,LI Yu-sheng,CHEN Xiao-bing,et al.Numerical Simulation for the Problem of Project Slope Toppling Deformation on the Right Abutment of a Hydropower Station Dam on Lancang River[J].Journal of Engineering Geology,2008,16(8):298-303.(in Chinese))
[8]陈孝兵,李渝生,赵小平.底摩擦重力试验在倾倒变形岩体稳定性研究中的应用[J].地学前缘,2008,15(2):300-304.(CHEN Xiao-bing,LI Yu-sheng,ZHAO Xiao-ping.The Application of Bottom Friction Gravity Test to the Study of the Toppling Rock Mass[J].Earth Science Frontiers,2008,15(2):300-304.(in Chinese))
[9]蔡国军,黄润秋,严明,等.反倾向边坡开挖变形破裂响应的物理模拟研究[J].岩石力学与工程学报,2008,27(4):812-817.(CAI Guo-jun,HUANG Run-qiu,YAN Ming,et al.Physical Simulation on Deformation and Failure Response of an Anti-inclined Slope during Excavation[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(4):812-817.(in Chinese))
[10]韩贝传,王思敬.边坡倾倒变形的形成机制与影响因素分析[J].工程地质学报,1999,7(3):213-217.(HAN Bei-chuan,WANG Si-jing.Mechanism for Toppling Deformation of Slope and Analysis of Influencing Factors on It[J].Journal of Engineering Geology,1999,7(3):213-217.(in Chinese))
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