地震波效应与山体斜坡震裂机理深入分析
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摘要
"5·12"汶川大地震造成了大量山体斜坡震裂变形和破坏现象,为深入研究其力学机理,通过实例详细调查及地震中体波效应和面波效应的深入分析,认为地震中地震波的作用使山体斜坡表部岩土体尤其是坡肩部位受到量值和方向不断变化的拉张应力作用,该作用在垂直平面内表现为全方位动态变化特点,导致坡肩岩土体具有旋转倾倒和正、反拉作用;与此同时在坡体内部伴随出现潜在剪动作用力及岩土体的开裂和压碎现象,尤其在潜在滑动面上剪切作用力更为集中;此外坡体表面还受到鼓胀拉力和扭力的共同作用。据此可将地震波作用效应划分为4种重要表现形式,即拉-剪破裂效应、界面动应力效应、潜在的楔劈效应和超空(孔)隙水压力激发机制。分析结果与实例及振动模拟结果一致。研究成果可为灾后重建和防灾减灾提供参考。
On the basis of the phenomena of slope shattered deformation and failure after 5·12 Wenchuan great earthquake,the effects of body wave and surface wave in the earthquake are analyzed,and the mechanical mechanism of slope shattered deformation are studied.It is considered that the effect of seismic waves caused the alternate action of the tension stress with values and direction constantly changing acted on the rock and soil mass of slope surface layer,especially on the slope shoulder,the characteristic on perpendicular plane showed overall dynamic change and resulted in the rock and soil mass on shoulder appeared revolution-dump,positive and inverse tension action.Meanwhile,the following shear action,cracking and crushing occurred.The shear action was more concentrated on slide surface.In addition,the bulge tension and torsion forces acted together on the slope surface also.In this paper,seismic wave effect is divided into four kinds of forms: the tension-shearing rupture effect,the interface dynamic stress effect,the potential wedge splitting effect,and the super interstitial hydraulic or pore water pressure excitation mechanism.The analysis results are well in accordance with field phenomena and the result of vibration simulation model,provided an important guide for the post-disaster reconstruction and disaster prevention and mitigation.
On the basis of the phenomena of slope shattered deformation and failure after 5·12 Wenchuan great earthquake,the effects of body wave and surface wave in the earthquake are analyzed,and the mechanical mechanism of slope shattered deformation are studied.It is considered that the effect of seismic waves caused the alternate action of the tension stress with values and direction constantly changing acted on the rock and soil mass of slope surface layer,especially on the slope shoulder,the characteristic on perpendicular plane showed overall dynamic change and resulted in the rock and soil mass on shoulder appeared revolution-dump,positive and inverse tension action.Meanwhile,the following shear action,cracking and crushing occurred.The shear action was more concentrated on slide surface.In addition,the bulge tension and torsion forces acted together on the slope surface also.In this paper,seismic wave effect is divided into four kinds of forms: the tension-shearing rupture effect,the interface dynamic stress effect,the potential wedge splitting effect,and the super interstitial hydraulic or pore water pressure excitation mechanism.The analysis results are well in accordance with field phenomena and the result of vibration simulation model,provided an important guide for the post-disaster reconstruction and disaster prevention and mitigation.
引文
[1]石玉成,卢育霞.汶川8.0级地震甘肃灾区震害特点及恢复重建对策[J].西北地震学报,2009,31(1):1-7.
[2]王爱国,杨晓鹏,李明永,等.汶川MS8.0地震对甘肃陇东地区的破坏影响与特征分析[J].西北地震学报,2009,31(1):80-85.
[3]Sujoy Ghose,Robert J Mellors,Andrei M Korjenkov,etc.The MS=7.3 1992Suusamyr,Kyrgyzstan,Earthquake in theTien Shan:Aftershock Focal Mechanisms and Surface De-formation[J].Bulletin of the Seismological Society of Ameri-ca,1997,87(1):23-38.
[4]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):279-2797.
[5]何丽君,石玉成,杨惠林,等.地震动作用下黄土边坡稳定性分析[J].西北地震学报,2009,31(2):142-147.
[6]安永林,彭立敏,黄娟.地震时隧道衬砌受力敏感性的简化理论分析[J].西北地震学报,2008,30(3):261-265.
[7]Richard R,Elms D G.Seismic behavior of gravity retainingwalls[J].J.Geotech.Engng.Div.,1979,105(GT4):449-464.
[8]Lin J S,Whitman R V.Earthquake induced displacements ofsliding blocks[J].J.Geotech.Engng.Div.,1986,112(1):44-59.
[9]任自铭,冯仲林,殷世林.土质边坡剖面上动力响应异常点与潜在滑动面位置的关系研究[J].西北地震学报,2009,31(1):21-25.
[10]梁庆国,韩文峰.强震区岩体地震动力破坏特征[J].西北地震学报,2009,31(1):15-20.
[11]冯文凯,许强,黄润秋.斜坡震裂变形力学机制初探[J].岩石力学与工程学报,2009,28(增1):3124-3130.
[12]许向宁.高地震烈度区山体变形破裂机制地质分析与地质力学模拟研究[D].成都理工大学,2006.
[13]秋仁东,石玉成,付长华.高边坡在水平动荷载作用下的动力响应规律研究[J].世界地震工程,2007,23(2):131-138.
[14]杨明,姚令侃,王建,等.斜坡堆积体抗震加固措施离心模型试验[J].西南交通大学学报,2008,43(3):335-340.
[15]黄润秋.岩石高边坡发育的动力过程及其稳定性控制[J].岩石力学与工程学报,2008,27(8):1525-1544.
[16]高广运,彭争光,张梦芳,等.层状地基空沟被动隔振分析[J].西北地震学报,2009,31(2):115-120.
[17]张悼元,王士天,王兰生.工程地质分析原理[M].北京:地质出版社,1994.
[2]王爱国,杨晓鹏,李明永,等.汶川MS8.0地震对甘肃陇东地区的破坏影响与特征分析[J].西北地震学报,2009,31(1):80-85.
[3]Sujoy Ghose,Robert J Mellors,Andrei M Korjenkov,etc.The MS=7.3 1992Suusamyr,Kyrgyzstan,Earthquake in theTien Shan:Aftershock Focal Mechanisms and Surface De-formation[J].Bulletin of the Seismological Society of Ameri-ca,1997,87(1):23-38.
[4]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):279-2797.
[5]何丽君,石玉成,杨惠林,等.地震动作用下黄土边坡稳定性分析[J].西北地震学报,2009,31(2):142-147.
[6]安永林,彭立敏,黄娟.地震时隧道衬砌受力敏感性的简化理论分析[J].西北地震学报,2008,30(3):261-265.
[7]Richard R,Elms D G.Seismic behavior of gravity retainingwalls[J].J.Geotech.Engng.Div.,1979,105(GT4):449-464.
[8]Lin J S,Whitman R V.Earthquake induced displacements ofsliding blocks[J].J.Geotech.Engng.Div.,1986,112(1):44-59.
[9]任自铭,冯仲林,殷世林.土质边坡剖面上动力响应异常点与潜在滑动面位置的关系研究[J].西北地震学报,2009,31(1):21-25.
[10]梁庆国,韩文峰.强震区岩体地震动力破坏特征[J].西北地震学报,2009,31(1):15-20.
[11]冯文凯,许强,黄润秋.斜坡震裂变形力学机制初探[J].岩石力学与工程学报,2009,28(增1):3124-3130.
[12]许向宁.高地震烈度区山体变形破裂机制地质分析与地质力学模拟研究[D].成都理工大学,2006.
[13]秋仁东,石玉成,付长华.高边坡在水平动荷载作用下的动力响应规律研究[J].世界地震工程,2007,23(2):131-138.
[14]杨明,姚令侃,王建,等.斜坡堆积体抗震加固措施离心模型试验[J].西南交通大学学报,2008,43(3):335-340.
[15]黄润秋.岩石高边坡发育的动力过程及其稳定性控制[J].岩石力学与工程学报,2008,27(8):1525-1544.
[16]高广运,彭争光,张梦芳,等.层状地基空沟被动隔振分析[J].西北地震学报,2009,31(2):115-120.
[17]张悼元,王士天,王兰生.工程地质分析原理[M].北京:地质出版社,1994.
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