地震纵横波时差耦合作用的斜坡崩滑效应研究
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摘要
多次典型地震的灾后实地调查都表明震中附近的竖向地震力作用十分明显,而传统的斜坡动力响应分析仅考虑了水平地震力的作用。文中运用离散元数值模拟技术,对震中附近的斜坡体在具地域性和空间非均质性的地震纵横波时差耦合作用下产生崩滑破坏的动力全过程进行了研究,确定了地震动力作用触发的震中附近斜坡体崩滑破坏的形成机制及主控因素。研究表明:对于地震作用下震中附近的斜坡体崩滑破坏,由于纵横波作用的时间差较短,其崩滑形成机制多为受地震纵横波的耦合作用,即竖向周期拉压与水平周期剪切的耦合作用,在此基础上又以纵波的竖向拉伸作用占优,即表现为拉剪破坏形式;此外,在地震构造组合机制、岩体结构与构造、斜坡岩体风化程度及物理力学参数等因素既定的情况下,地震力作用(即地震纵波的周期拉压和地震横波的周期剪切耦合作用)是诱发斜坡体产生初期崩滑破坏的主控因素,而斜坡所处地形(如高程差、沟谷延伸方向)则是促使破坏后的斜坡体形成后续碰撞解体及碎屑流等运动过程的控制诱发因素。
Field geological investigations after earthquakes show that the effect of vertical seismic force is very evident,whereas only the effect of horizontal seismic force is concerned in conventional analysis of dynamic response of slopes.Collapsing and sliding responses of slope near epicenter and its running out process triggered by single and combined actions with time difference,local condtions and spatial heterogeneity of P and S seismic waves are elaborated.The formation mechanism and key controlling factors of the slope collapsing and sliding are confirmed.The result of numerical simulation shows that the slope collapsing and sliding are triggered by the combined action of seismic P-and S-waves,i.e.the coupled effect of vertical periodic tension and compression and horizontal periodic shearing.For the vertical tension of P-wave is dominant,tension and shear fractures would appear in slope body.On the other hand,combined action between periodic tension and compression of P-wave and periodic shearing of S-wave is the key controlling factor inducing slope collapsing and sliding on the conditions of known seismic tectonics,structure and tectonics of slope mass,weathering degree of rock mass and physical and mechanical parameters of slope body.At the same time,slope topography is the key controlling factor leading to collision and debris flow of slope mass fractured in latter process.It is of great theoretical and practical value in studying collapsing and sliding of slope triggered by seismic loads.
Field geological investigations after earthquakes show that the effect of vertical seismic force is very evident,whereas only the effect of horizontal seismic force is concerned in conventional analysis of dynamic response of slopes.Collapsing and sliding responses of slope near epicenter and its running out process triggered by single and combined actions with time difference,local condtions and spatial heterogeneity of P and S seismic waves are elaborated.The formation mechanism and key controlling factors of the slope collapsing and sliding are confirmed.The result of numerical simulation shows that the slope collapsing and sliding are triggered by the combined action of seismic P-and S-waves,i.e.the coupled effect of vertical periodic tension and compression and horizontal periodic shearing.For the vertical tension of P-wave is dominant,tension and shear fractures would appear in slope body.On the other hand,combined action between periodic tension and compression of P-wave and periodic shearing of S-wave is the key controlling factor inducing slope collapsing and sliding on the conditions of known seismic tectonics,structure and tectonics of slope mass,weathering degree of rock mass and physical and mechanical parameters of slope body.At the same time,slope topography is the key controlling factor leading to collision and debris flow of slope mass fractured in latter process.It is of great theoretical and practical value in studying collapsing and sliding of slope triggered by seismic loads.
引文
[1]殷跃平.汶川八级地震地质灾害研究[J].工程地质学报,2008,16(4):433～444.Yin Yueping.Research on the geo-hazards triggered by Wen-chuan Earthquake,Sichuan.Journal of Engineering Geology,2008,16(4):433～444.
[2]殷跃平,等.汶川地震地质与滑坡灾害概论[M].北京:地质出版社,2009.Yin Yueping,et al..Introduction of seismic geology and landslide hazard triggered by the Wenchuan Earthquake.Beijing:Geological Publishing House,2009.
[3]胡广韬,毛彦龙,程谦恭,等.地震时滑坡体波动震荡的启程加速动力学问题[R].西安:西安工程学院,1997.Hu Guangtao,Mao Yanlong,Cheng Qiangong,et al..Set-out violent-slide dynamic problems of slope shaking during an earth-quake.Xi′an:Xi′an Engineering University,1997.
[4]林淋.竖向地震动特征分析[D].哈尔滨:中国地震局工程力学研究所,2005.Lin Lin.Characteristics analysis of vertical ground motion.Ha-erbin:Institute of Engineering Mechnics,China Earthquake Ad-ministration,2005.
[5]崔芳鹏.地震P-S波时差耦合作用的斜坡崩滑效应研究[D].北京:中国科学院地质与地球物理研究所,2009.Cui Fangpeng.Study on collapsing and sliding response of slope triggered by single and combined action with time difference of P and S seismic waves.Beijing:Institute of Geology and Geophys-ics,Chinese Academy of Science,2009.
[6]周维垣.高等岩石力学[M].北京:水利电力出版社,1990.Zhou Weiyuan.Higher rock mechanics.Beijing:Water Resources and Electric Power Publishing House,1990.
[7]张倬元,王士天,王兰生.工程地质分析原理[M].北京:地质出版社,1993.Zhang Zhuoyuan,Wang Shitian,Wang Lansheng.Analytical the-ory of engineering geology.Beijing:Geological Publishing House,1993.
[8]胡光韬.滑坡动力学[M].北京:地质出版社,1995.Hu Guangtao.Dynamic landslide.Beijing:Geological Publishing House,1995.
[9]毛彦龙,胡广韬,毛新虎,等.地震滑坡启程剧动的机理研究及离散元模拟[J].工程地质报,2001,9(1):74～80.Mao Yanlong,Hu Guangtao,Mao Xinhu,et al..Mechanism of set-out violent-slide of slope mass during earthquake and its simulation by using discrete element method.Journal of Engineer-ing Geology,2001,9(1):74～80.
[10]祁生文,伍法权,刘春玲,等.地震边坡稳定性的工程地质分析[J].岩石力学与工程学报,2004,23(16):2792～2796.Qi Shenwen,Wu Faquan,Liu Chunling,et al..Engineering ge-ology analysis on stability of slope under earthquake.Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2792～2796.
[11]杜晓丽.地震荷载作用下岩质边坡稳定性研究[D].西安:西安科技大学,2008.Du Xiaoli.Research on the stability of rock slope under seismic loadings.Xian:Xi′an University of Science and Technology,2008.
[12]徐光兴,姚令侃,高召宁,等.边坡动力特性与动力响应的大型振动台模型试验研究[J].岩石力学与工程学报,2008,27(3):624～632.Xu Guangxing,Yao Lingkan,Gao Zhaoning,et al..Large-scale shaking table model test study on dynamic characteristics and dynamic response of slope.Chinese Journal of Rock Mechan-ics and Engineering,2008,27(3):624～632.
[13]徐光兴,姚令侃,李朝红,等.边坡地震动力响应规律及地震动参数影响研究[J].岩土工程学报,2008,30(6):918～923.Xu Guangxing,Yao Lingkan,Li Chaohong,et al..Dynamic re-sponse of slopes under earthquakes and influence of ground mo-tion parameters.Chinese Journal of Geotechnical Engineering,2008,30(6):918～923.
[14]许强,黄润秋.5.12汶川大地震诱发大型崩滑灾害动力特征初探[J].工程地质学报,2008,16(6):721～729.XUQiang,Huang Runqiu.Kinetics characteristics of large land-slides triggered by May12Wenchuan Earthquake.Journal of En-gineering Geology,2008,16(6):721～729.
[15]Itasca Consulting Group,Inc.Universal Distinct Element Code Theory and background.Mill Place,2005.
[16]殷跃平.汶川八级地震滑坡特征分析[J].工程地质学报,2009,17(1):29～38.Yin Yueping.Fearures of landslides triggered by the Wenchuan Earthquake.Journal of Engineering Geology,2009,17(1):29～38
[17]谢和平,邓建辉,台佳佳,等.汶川大地震灾害与灾区重建的岩土工程问题[J].岩石力学与工程学报,2008,27(9):1781～1791.Xie Heping,Deng Jianhui,Tai Jiajia,et al.Wenchuan large earthquake and post-earthquake reconstruction-related geotechnical problems.Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781～1791.
[18]胡聿贤.地震工程学[M].北京:地震出版社,1988.Hu Yuxian.Earthquake engineering.Beijing,Seismologic Press,1988.
[2]殷跃平,等.汶川地震地质与滑坡灾害概论[M].北京:地质出版社,2009.Yin Yueping,et al..Introduction of seismic geology and landslide hazard triggered by the Wenchuan Earthquake.Beijing:Geological Publishing House,2009.
[3]胡广韬,毛彦龙,程谦恭,等.地震时滑坡体波动震荡的启程加速动力学问题[R].西安:西安工程学院,1997.Hu Guangtao,Mao Yanlong,Cheng Qiangong,et al..Set-out violent-slide dynamic problems of slope shaking during an earth-quake.Xi′an:Xi′an Engineering University,1997.
[4]林淋.竖向地震动特征分析[D].哈尔滨:中国地震局工程力学研究所,2005.Lin Lin.Characteristics analysis of vertical ground motion.Ha-erbin:Institute of Engineering Mechnics,China Earthquake Ad-ministration,2005.
[5]崔芳鹏.地震P-S波时差耦合作用的斜坡崩滑效应研究[D].北京:中国科学院地质与地球物理研究所,2009.Cui Fangpeng.Study on collapsing and sliding response of slope triggered by single and combined action with time difference of P and S seismic waves.Beijing:Institute of Geology and Geophys-ics,Chinese Academy of Science,2009.
[6]周维垣.高等岩石力学[M].北京:水利电力出版社,1990.Zhou Weiyuan.Higher rock mechanics.Beijing:Water Resources and Electric Power Publishing House,1990.
[7]张倬元,王士天,王兰生.工程地质分析原理[M].北京:地质出版社,1993.Zhang Zhuoyuan,Wang Shitian,Wang Lansheng.Analytical the-ory of engineering geology.Beijing:Geological Publishing House,1993.
[8]胡光韬.滑坡动力学[M].北京:地质出版社,1995.Hu Guangtao.Dynamic landslide.Beijing:Geological Publishing House,1995.
[9]毛彦龙,胡广韬,毛新虎,等.地震滑坡启程剧动的机理研究及离散元模拟[J].工程地质报,2001,9(1):74～80.Mao Yanlong,Hu Guangtao,Mao Xinhu,et al..Mechanism of set-out violent-slide of slope mass during earthquake and its simulation by using discrete element method.Journal of Engineer-ing Geology,2001,9(1):74～80.
[10]祁生文,伍法权,刘春玲,等.地震边坡稳定性的工程地质分析[J].岩石力学与工程学报,2004,23(16):2792～2796.Qi Shenwen,Wu Faquan,Liu Chunling,et al..Engineering ge-ology analysis on stability of slope under earthquake.Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2792～2796.
[11]杜晓丽.地震荷载作用下岩质边坡稳定性研究[D].西安:西安科技大学,2008.Du Xiaoli.Research on the stability of rock slope under seismic loadings.Xian:Xi′an University of Science and Technology,2008.
[12]徐光兴,姚令侃,高召宁,等.边坡动力特性与动力响应的大型振动台模型试验研究[J].岩石力学与工程学报,2008,27(3):624～632.Xu Guangxing,Yao Lingkan,Gao Zhaoning,et al..Large-scale shaking table model test study on dynamic characteristics and dynamic response of slope.Chinese Journal of Rock Mechan-ics and Engineering,2008,27(3):624～632.
[13]徐光兴,姚令侃,李朝红,等.边坡地震动力响应规律及地震动参数影响研究[J].岩土工程学报,2008,30(6):918～923.Xu Guangxing,Yao Lingkan,Li Chaohong,et al..Dynamic re-sponse of slopes under earthquakes and influence of ground mo-tion parameters.Chinese Journal of Geotechnical Engineering,2008,30(6):918～923.
[14]许强,黄润秋.5.12汶川大地震诱发大型崩滑灾害动力特征初探[J].工程地质学报,2008,16(6):721～729.XUQiang,Huang Runqiu.Kinetics characteristics of large land-slides triggered by May12Wenchuan Earthquake.Journal of En-gineering Geology,2008,16(6):721～729.
[15]Itasca Consulting Group,Inc.Universal Distinct Element Code Theory and background.Mill Place,2005.
[16]殷跃平.汶川八级地震滑坡特征分析[J].工程地质学报,2009,17(1):29～38.Yin Yueping.Fearures of landslides triggered by the Wenchuan Earthquake.Journal of Engineering Geology,2009,17(1):29～38
[17]谢和平,邓建辉,台佳佳,等.汶川大地震灾害与灾区重建的岩土工程问题[J].岩石力学与工程学报,2008,27(9):1781～1791.Xie Heping,Deng Jianhui,Tai Jiajia,et al.Wenchuan large earthquake and post-earthquake reconstruction-related geotechnical problems.Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781～1791.
[18]胡聿贤.地震工程学[M].北京:地震出版社,1988.Hu Yuxian.Earthquake engineering.Beijing,Seismologic Press,1988.
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