地震纵横波时差耦合作用的斜坡崩滑响应研究
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摘要
运用离散元数值模拟技术,对北川新中崩滑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,确定了该斜坡体在强震动力作用下产生崩滑破坏的形成机制及主控因素。研究表明:①对于新中崩滑体的先期崩滑破坏而言,由于其距离初始震中较远,故源自初始震源的地震纵横波到达该斜坡体的时差较长,为约15.21 s,而该斜坡体在地震纵波作用于斜坡体后8 s后即开始破裂,故其先期崩滑破坏是受到地震纵波产生的水平与竖向拉裂耦合作用所致,并以水平拉裂作用占优,而后期的抛射及运动过程则是受到地震纵横波的耦合作用所致;②对其发生先期崩滑的主控因素言,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,地震纵波产生的水平与竖向拉裂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;③该斜坡体动力响应特征值的放大效应表明,其放大系数值从大到小依次是水平加速度>竖向加速度>水平速度>竖向速度,该结果与斜坡体发生先期崩滑破坏的形成机制及主控因素相符合,即地震纵波产生的水平加速度起到了优势破坏作用。以上研究为强震动力作用下的斜坡体先期崩滑破坏提供了新方法。
The collapsing and sliding response of Xinzhong slope in Beichuan County and its collapsing process triggered by the single and combined action with time difference and the regionality and spatial heterogeneity of P and S seismic waves are studied.The formation mechanism and key factors are determined by applying DEM numerical simulation.The results show that the initial collapsing and sliding of the slope in running time,i.e.8 seconds of numerical model,is triggered by the combined action of horizontal and vertical tensions caused by P seismic waves because of their relatively long distance from the initial epicenter inducing larger difference,i.e.15.21 seconds in time,which P and S seismic waves consume from the hypocenter to the slope.What’s more,the horizontal tension plays a superior role.Ejecting and flowing of the broken slope mass is triggered by the combined action of P and S seismic waves.Secondly,the combined action between horizontal and vertical tensions of P waves is the key factor inducing the collapsing and sliding of the slope under the known seismic tectonics,structure and tectonics of slope mass,weathering degree of rock mass as well as the physical and mechanical parameters of slope body.At the same time,the slope topography is the key factor leading to collision and debris flow of the slope mass fractured in latter process.Finally,the amplification effect of parameters in dynamic response of the slope shows that the amplification coefficient of horizontal acceleration is larger than that of vertical acceleration.The horizontal velocity and the vertical velocity decrease one by one,and this trend is consistent with the key factor inducing slope fracturing,i.e.horizontal seismic loads play a superior role.It provides a new method for studies on the initial collapsing and sliding of slopes triggered by seismic loads.
The collapsing and sliding response of Xinzhong slope in Beichuan County and its collapsing process triggered by the single and combined action with time difference and the regionality and spatial heterogeneity of P and S seismic waves are studied.The formation mechanism and key factors are determined by applying DEM numerical simulation.The results show that the initial collapsing and sliding of the slope in running time,i.e.8 seconds of numerical model,is triggered by the combined action of horizontal and vertical tensions caused by P seismic waves because of their relatively long distance from the initial epicenter inducing larger difference,i.e.15.21 seconds in time,which P and S seismic waves consume from the hypocenter to the slope.What’s more,the horizontal tension plays a superior role.Ejecting and flowing of the broken slope mass is triggered by the combined action of P and S seismic waves.Secondly,the combined action between horizontal and vertical tensions of P waves is the key factor inducing the collapsing and sliding of the slope under the known seismic tectonics,structure and tectonics of slope mass,weathering degree of rock mass as well as the physical and mechanical parameters of slope body.At the same time,the slope topography is the key factor leading to collision and debris flow of the slope mass fractured in latter process.Finally,the amplification effect of parameters in dynamic response of the slope shows that the amplification coefficient of horizontal acceleration is larger than that of vertical acceleration.The horizontal velocity and the vertical velocity decrease one by one,and this trend is consistent with the key factor inducing slope fracturing,i.e.horizontal seismic loads play a superior role.It provides a new method for studies on the initial collapsing and sliding of slopes 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 Yue-ping.Research on the geo-hazards triggered by Wenchuan Earthquake,Sichuan[J].Journal of Engineering Geology,2008,16(4):433–444.(in Chinese))
[2]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 Fang-peng.Study on collapsing and sliding response of slope triggered by single and combined action with time difference of P and S seismic waves[D].Beijing:Institute of Geology and Geophysics,Chinese Academy of Science,2009.(in Chinese))
[3]周维垣.高等岩石力学[M].北京:水利电力出版社,1990.(ZHOU Wei-yuan.Higher rock mechanics[M].Beijing:Water Resources and Electric Power Publishing House,1990.(in Chinese))
[4]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 Zhuo-yuan,WANG Shi-tian,WANG Lan-sheng.Analytical theory of engineering geology[M].Beijing:Geological Publishing House,1993.(in Chinese))
[5]胡光韬.滑坡动力学[M].北京:地质出版社,1995.(HU Guang-tao.Dynamic landslide[M].Beijing:Geological Publishing House,1995.(in Chinese))
[6]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 Yan-long,HU Guang-tao,MAO Xin-hu,et al.Mechanism of set-out violent-slide of slope mass during earthquake and its simulation by using discrete element method[J].Journal of Engineering Geology,2001,9(1):74–80.(in Chinese))
[7]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 Shen-wen,WU Fa-quan,LIU Chun-ling,et al.Engineering geology analysis on stability of slope under earthquake[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2792–2796.(in Chinese))
[8]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 Guang-tao,MAO Yan-long,CHENG Qian-gong,et al.Set-out violent-slide dynamic problems of slope shaking during an earthquake[R].Xi'an:Xi'an Engineering University,1997.(in Chinese))
[9]李杰,李国强.地震工程学导论[M].北京:地震出版社,1992.(LI Jie,LI Guo-qiang.Introduction of earthquake engineering[M].Beijing:Seismological Publishing House,1992.(in Chinese))
[10]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 Guang-xing,YAO Ling-kan,GAO Zhao-ning,et al.Large-scale shaking table model test study on dynamic characteristics and dynamic response of slope[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(3):624–632.(in Chinese))
[11]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 Guang-xing,YAO Ling-kan,LI Chao-hong,et al.Dynamic response of slopes under earthquakes and influence of ground motion parameters[J].Chinese Journal of Geotechnical Engineering,2008,30(6):918–923.(in Chinese))
[12]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[J].Journal of Engineering Geology,2009,17(1):29–38.(in Chinese))
[13]Itasca Consulting Group,Inc.Universal distinct element code theory and background[M].Mill Place,2005.
[14]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 He-ping,DENG Jian-hui,TAI Jia-jia,et al.Wenchuan large earthquake and post-earthquake reconstruction-related geotechnical problems[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781–1791.(in Chinese))
[15]胡聿贤.地震工程学[M].北京:地震出版社,1988.(HU Yu-xian.Earthquake engineering[M].Beijing:Seismological Publishing House,1988.(in Chinese))
[16]小屁牛.科学松鼠会.[2008-05-07].http://songshuhui.net/archives/224.html[EB/OL].
[2]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 Fang-peng.Study on collapsing and sliding response of slope triggered by single and combined action with time difference of P and S seismic waves[D].Beijing:Institute of Geology and Geophysics,Chinese Academy of Science,2009.(in Chinese))
[3]周维垣.高等岩石力学[M].北京:水利电力出版社,1990.(ZHOU Wei-yuan.Higher rock mechanics[M].Beijing:Water Resources and Electric Power Publishing House,1990.(in Chinese))
[4]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 Zhuo-yuan,WANG Shi-tian,WANG Lan-sheng.Analytical theory of engineering geology[M].Beijing:Geological Publishing House,1993.(in Chinese))
[5]胡光韬.滑坡动力学[M].北京:地质出版社,1995.(HU Guang-tao.Dynamic landslide[M].Beijing:Geological Publishing House,1995.(in Chinese))
[6]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 Yan-long,HU Guang-tao,MAO Xin-hu,et al.Mechanism of set-out violent-slide of slope mass during earthquake and its simulation by using discrete element method[J].Journal of Engineering Geology,2001,9(1):74–80.(in Chinese))
[7]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 Shen-wen,WU Fa-quan,LIU Chun-ling,et al.Engineering geology analysis on stability of slope under earthquake[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(16):2792–2796.(in Chinese))
[8]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 Guang-tao,MAO Yan-long,CHENG Qian-gong,et al.Set-out violent-slide dynamic problems of slope shaking during an earthquake[R].Xi'an:Xi'an Engineering University,1997.(in Chinese))
[9]李杰,李国强.地震工程学导论[M].北京:地震出版社,1992.(LI Jie,LI Guo-qiang.Introduction of earthquake engineering[M].Beijing:Seismological Publishing House,1992.(in Chinese))
[10]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 Guang-xing,YAO Ling-kan,GAO Zhao-ning,et al.Large-scale shaking table model test study on dynamic characteristics and dynamic response of slope[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(3):624–632.(in Chinese))
[11]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 Guang-xing,YAO Ling-kan,LI Chao-hong,et al.Dynamic response of slopes under earthquakes and influence of ground motion parameters[J].Chinese Journal of Geotechnical Engineering,2008,30(6):918–923.(in Chinese))
[12]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[J].Journal of Engineering Geology,2009,17(1):29–38.(in Chinese))
[13]Itasca Consulting Group,Inc.Universal distinct element code theory and background[M].Mill Place,2005.
[14]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 He-ping,DENG Jian-hui,TAI Jia-jia,et al.Wenchuan large earthquake and post-earthquake reconstruction-related geotechnical problems[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(9):1781–1791.(in Chinese))
[15]胡聿贤.地震工程学[M].北京:地震出版社,1988.(HU Yu-xian.Earthquake engineering[M].Beijing:Seismological Publishing House,1988.(in Chinese))
[16]小屁牛.科学松鼠会.[2008-05-07].http://songshuhui.net/archives/224.html[EB/OL].
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