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| Analysis of failure mechanism of Qianjiangping slope based on improved failure approach index |
| ZHANG Zhenhua1，2，QIAN Mingming1，WEI Wei3 |
(1. School of Civil Engineering，Hefei University of Technology，Hefei，Anhui 230009，China；2. Collaborative Innovation Center for Geo-hazards and Eco-environment in Three Gorges Area，Yichang，Hubei 443002，China；3. School of Civil
Engineering，Wuhan University，Wuhan，Hubei 430072，China) |
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Abstract Qianjiangping landslide is the first large scale rock slide in the area of Three Gorges Reservoir(TGR) after impoundment. Most of the researchers agreed in the previous studies that reservoir impoundment and rainfall were two main factors triggering the landslide. However，there were different views regarding the degree of influence of two factors on the failure of the landslide，one considered that the influence of reservoir impoundment was greater than that of rainfall，the other considered that the influence of rainfall was greater than that of reservoir impoundment. In order to clarify this issue，the rock near the rock bridge that was part of the slip zone after sliding was selected. The triaxial compression tests on the influence of reservoir water immersion on strength and deformation of rock mass were carried out. The seepage field of groundwater and stresses in the slope under three conditions(reservoir impoundment，rainfall，and combined effect of reservoir impoundment and rainfall) were calculated with the software ABAQUS. Failure approach index was improved based on the constitutive relation of the rock obtained experimentally，and the improved failure approach index was applied to analyze the failure characteristics of the landslide under each condition. Under the influence of reservoir impoundment，the elastic modulus and shear strength of rock decrease remarkably when the rock is soaked. The influence of rainfall is greater than that of reservoir impoundment on the failure of the landslide，and the influence of combined effect of reservoir impoundment and rainfall is greater than that of rainfall. The sliding surface runs through under the combined effect of reservoir impoundment and rainfall. The study results suggest that the water immersion after reservoir impoundment reduced the strength of discontinuous rock bridges in the gently dipping discontinuous structural plane at the toe of the slope，the rainfall increased the sliding force of the slope，finally，the rock bridges fractured，and the failure of the slope occurred.
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[1] WANG F W，ZHANG Y M，HUO Z T，et al. Mechanism for the rapid motion of the Qianjiangping landslide during reactivation by the first impoundment of the Three Gorges Dam reservoir，China[J]. Landslides，2008，5(4)：379–386.
[2] 肖诗荣，王世梅，胡志宇，等. 千将坪滑坡地质力学模型研究[R]. 宜昌：三峡库区地质灾害防治工作指挥部，2007.(XIAO Shirong，WANG Shimei，HU Zhiyu，et al. Research report on geomechanical model of Qianjiangping landslide[R]. Yichang：The Chinese Journal of Geological Hazard and Control，China，2007.(in Chinese))
[3] 李会中，王团乐，孙立华，等. 三峡库区千将坪滑坡地质特征与成因机制分析[J]. 岩土力学，2006，27(增2)：1 239–1 244.(LI Huizhong，WANG Tuanle，SUN Lihua，et al. Characteristics and mechanism of Qianjiangping Landslide in Three Gorges Reservoir Area[J]. Rock and Soil Mechanics，2006，27(Supp.2)：1 239– 1 244.(in Chinese))
[4] 李会中，潘玉珍，王团乐，等. 三峡库区千将坪滑坡成因与机制分析[J]. 人民长江，2006，37(7)：12–14+20.(LI Huizhong，PAN Yuzhen，WANG Tuanle，et al. Analysis on the cause and mechanism of Qianjiangping Landslide in Three Gorges Reservoir Area[J]. Yangtze Rive，2006，37(7)：12–14+20.(in Chinese))
[5] 杨海平，王金生. 长江三峡工程库区千将坪滑坡地质特征及成因分析[J]. 工程地质学报，2009，17(2)：233–239.(YANG Haiping，WANG Jinsheng. Geological features and cause analysis of Qianjiangping Landslide[J]. Journal of Engineering Geology，2009，17(2)：233–239.(in Chinese))
[6] WANG F W，ZHANG Y M，HUO Z T，et al. The July 14，2003 Qianjiangping landslide，Three Gorges Reservoir，China[J]. Landslides，2004，1(2)：157–162.
[7] DAI F C，DENG J H，THAM L G，et al. A large landslide in Zigui County，Three Gorges area[J]. Canadian Geotechnical Journal，2004，41(6)：1 233–1 240.
[8] 杨为民，吴树仁，石菊松，等. 湖北秭归千将坪岩质滑坡形成机理分析[J]. 煤炭工程，2006，37(4)：57–59.(YANG Weiming，WU Shuren，SHI Jusong，et al. Analysis on the formation mechanism of Qianjiangping landslide in Zigui County Hubei province[J]. Coal Engineering，2006，37(4)：57–59.(in Chinese))
[9] JIANG Q H，ZHANG Z H，WEI W. Research on triggering mechanism and kinematic process of Qianjiangping Landslide[J]. Disaster Advances，2012，5(4)：631–636.
[10] 邬爱清，丁秀丽，李会中，等. 非连续变形分析方法模拟千将坪滑坡启动与滑坡全过程[J]. 岩石力学与工程学报，2006，25(7)：1 297–1 303.(WU Aiqing，DING Xiuli，LI Huizhong，et al. Numerical simulation of startup and whole failure process of Qianjingping Landslide using discontinuous deformation analysis method[J]. Chinese Journal of Rock Mechanics and Engineering，2006，25(7)：1 297–1 303.(in Chinese))
[11] JIAN W X，XU Q，YANG H F，et al. Mechanism and failure process of Qianjiangping landslide in the Three Gorges Reservoir，China[J]. Environmental Earth Sciences，2014，72(8)：2 999–3 013.
[12] 张钧强，罗先启，张振华. 千将坪滑坡变形特征及其机理研究[J] . 三峡大学学报：自然科学版，2007，29(5)：425–428.(ZHANG Junqiang，LUO Xianqi，ZHANG Zhenhua. Study on deformation characteristics and mechanism of Qianjiangping Landside[J]. Journal of China Three Gorges University：Natural Science，2007，29(5)：425–428.(in Chinese))
[13] 王治华，杨日红. 三峡水库区千将坪滑坡活动性质及运动特征[J] . 中国地质灾害与防治学报，2005，16(3)：5–11.(WANG Zhihua，YANG Rihong. The activity characteristics and movement style of Qianjiangping Landslide in the Three Gorges Reservoir region[J]. The Chinese Journal of Geological Hazard and Control，2005，16(3)：5–11.(in Chinese))
[14] 王治华，杨日红，王 毅. 秭归沙镇溪镇千将坪滑坡航空遥感调查[J]. 国土资源遥感，2003，15(3)：5–9+53–73.(WANG Zhihua，YANG Rihong，WANG Yi. An airborne remote sensing survey of Qianjiangping Landslide in Zigui Shaxisha town[J]. Remote Sensing for Land and Resource，2003，15(3)：5–9+53–73. (in Chinese))
[15] 杨日红，杨金中，王治华. 千将坪滑坡特征信息遥感提取及滑坡成因机理分析[J]. 地球与环境，2007，35(1)：85–90.(YANG Rihong，YANG Jinzhong，WANG Zhihua. The remote sensing image information interpretation and mechanism of Qianjiangping Landslide in Three Gorges[J]. Earth and Environment，2007，35(1)：85–90.(in Chinese))
[16] 文宝萍，申 健，谭建民. 水在千将坪滑坡中的作用机理[J]. 水文地质工程地质，2008，35(3)：12–18.(WEN Baoping，SHEN Jian，TAN Jianming. The influence of water on the occurrence of Qianjiangping landslide[J]. Hydrogeology and Engineering Geology，2008，35(3)：12–18.(in Chinese))
[17] 肖诗荣，刘德富，姜福兴，等. 三峡库区千将坪滑坡地质力学模型试验研究[J] . 岩石力学与工程学报，2010，29(5)：1 023–1 030. (XIAO Shirong，LIU Defu，JIANG Fuxing，et al. Geomechanical model experiment on Qianjiangping Landslide in Three Gorges Reservoie Area[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(5)：1 023–1 030.(in Chinese))
[18] 廖秋林，李 晓，李守定，等. 三峡库区千将坪滑坡的发生、地质地貌特征、成因及滑坡判据研究[J]. 岩石力学与工程学报，2005，24(17)：3 146–3 153.(LIAO Qiulin，LI Xiao，LI Shouding，et al. Occurrence，geology and geomorphy characteristics and origin of Qianjiangping Landslide in Three Gorges Reservoir Area and study on ancient landslide criterion[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(17)：3 146–3 153.(in Chinese))
[19] 三峡库区地质灾害防治工作指挥部. 湖北省秭归县沙镇溪镇千将坪滑坡[J]. 中国地质灾害与防治学报，2003，14(3)：139–142.(Headquarters of Geological Hazard Control in Area of the Three Gorges Reservoir. The Qianjiangping Landslide in Shazhenxi town Zigui county Hubei province[J]. The Chinese Journal of Geological Hazard and Control，2003，14(3)：139–142.(in Chinese))
[20] 肖诗荣，刘德富，胡志宇. 三峡库区千将坪滑坡地质力学模型研究[J]. 岩土力学，2007，28(7)：1 459–1 464.(XIAO Shirong，LIU Defu，HU Zhiyu. Study on geomechanical model of Qianjiangping landslide[J]. Three Gorges Reservoir. Rock and Soil Mechanics，2007，28(7)： 1 459–1 464.(in Chinese))
[21] 中华人民共和国行业标准编写组. SL264—2001水利水电工程岩石试验规程[S]. 北京：中国水利水电出版社，2001.(The Professional Standards Compilation Group of People?s Republic of China. SL264—2001 Specification for rock tests in water conservancy and hydroelectric engineering[S]. Beijing：China Water Power Press，2001.(in Chinese))
[22] 徐 晗，朱以文，蔡元奇，等. 降雨入渗条件下非饱和土边坡稳定分析[J]. 岩土力学，2005，26(12)：1 957–1 962.(XU Han，ZHU Yiwen，CAI Yuanqi，et al. Stability analysis of unsaturated soil slopes under rainfall infiltration[J]. Rock and Soil Mechanics，2005，26(12)：1 957–1 962.(in Chinese))
[23] 杨文东，张强勇，宋萌勃，等. 基于破坏接近度和强度折减法的边坡稳定性评价[J]. 山东大学学报：工学版，2010，40(6)：82–87. (YANG Wendong，ZHANG Qiangyong，SONG Mengbo，et al. Stability assessment of a high slope based on the failure approach index and strength reduction method[J]. Journal of Shandong University：Engineering Science，2010，40(6)：82–87.(in Chinese))
[24] ZHANG C Q，ZHOU H，FENG X T. An index for estimating the stability of brittle surrounding rock mass：FAI and its engineering application[J]. Rock Mechanics and Rock Engineering，2011，44(4)：401–414.
[25] 郑颖人，陈祖煜，王恭先，等. 边坡与滑坡工程治理[M]. 北京：人民交通出版社，2007：196–201.(ZHENG Yingren，CHEN Zuyu，WANG Gongxian，et al. Engineering treatment of slope and landslide[M]. Beijing：China Communications Press，2007：196–201.(in Chinese))
[26] 曹 玲，罗先启. 三峡库区千将坪滑坡滑带土干-湿循环条件下强度特性试验研究[J]. 岩土力学，2007，28(增1)：93–97.(CAO Ling，LUO Xianqi. Experimental study of dry-wet circulation of Qianjiangping Landslide?s unsaturated soil[J]. Rock and Soil Mechanics，2007，28(Supp.1)：93–97.(in Chinese))
[27] ZHANG C，FENG X，ZHOU H，et al. A Top pilot tunnel preconditioning method for the prevention of extremely intense rockbursts in deep tunnels excavated by TBMs[J]. Rock Mechanics and Rock Engineering，2012，45(3)：289–309.
[28] ZHANG C，FENG X T，ZHOU H，et al. Rockmass damage development following two extremely intense rockbursts in deep tunnels at Jinping II hydropower station，southwestern China[J]. Bulletin of Engineering Geology and the Environment，2013，72(2)：237–247.
[29] ZHANG C，FENG X T，ZHOU H，et al. Rock mass damage induced by rockbursts occurring on tunnel floors：a case study of two tunnels at the Jinping II Hydropower Station[J]. Environmental Earth Sciences，2014，71(1)：441–450.
[30] 王小平，夏 雄. 岩土类材料率相关性及硬化–软化特性模型研究[J]. 岩土力学，2011，32(11)：3 283–3 287.(WANG Xiaoping，XIA Xiong. Study of rate-dependence and hardening-softening characteristics of rock and soil material[J]. Rock and Soil Mechanics，2011，32(11)：3 283–3 287.(in Chinese))
[31] 周 勇，王 涛，吕 庆，等. 基于FLAC(3D)岩石应变软化模型的研究[J]. 长江科学院院报，2012，29(5)：51–56.(ZHOU Yong，WANG Tao，LV Qing，et al. Strain softening model of rock based on FLAC3D[J]. Journal of Yangtze River Scientific Research Institute，2012，29(5)：51–56.(in Chinese)) |
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2018, Vol. 37 
