反复微震作用下顺层及反倾岩质边坡的动力稳定性分析
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摘要
水库蓄水后诱发的高频次微小地震在一定程度上会对区域地质体的稳定性产生重要影响。本文采用振动台试验、UDEC数值分析方法,对顺层、反倾两类典型岩质边坡在反复微小地震作用下的动力稳定性进行了深入研究。结果表明:两类边坡的加速度响应均表现出"高程效应"和"趋表效应",且随地震作用次数的增加,坡体损伤(表现为层面与次级节理的起裂、扩展、贯通)不断累积,造成两类边坡的动力响应均呈现减弱的趋势;在反复微震作用下,边坡自振频率减低和阻尼比增大是其动力特性变化的基本规律;边坡累积永久位移随着地震作用次数的增加而增加,而稳定性系数则呈现递减趋势;在反复微震作用下,顺层坡的后缘竖向拉裂缝逐渐向下扩展并与下卧层面连通,边坡主要发生沿层面的整体滑移失稳模式;反倾坡首先在坡肩及坡面出现块体崩落,随后上部岩层逐层剥落,最终形成圆弧形破坏面,边坡以坡肩处发生落石、中上部岩层发生崩塌为主要破坏特征。
The high-frequency and micro earthquake induced by the Three Gorges Reservoir after impoundment will have an important influence on the stability of the regional geological body to a certain extent. The shaking table tests and UDEC numerical analysis method are used to analyze the dynamic stability of the typical bedding and toppling rock slopes under repeated micro earthquakes. The results show that the acceleration response of the two types of slopes exhibits the "elevation effect" and "surface effect", and with the increase of earthquake action frequency, the slope damage(manifested as the initiation, expansion and penetration of structural plane and secondary rock joint) accumulates continuously and the dynamic response of the two types of slopes decreases. Under the repeated micro earthquakes, the decrease of the natural frequency of the slopes and the increase of the damping ratio are the basic laws of the dynamic characteristics. The permanent displacement increases with the increase of earthquake action frequency, and the stability coefficient decreases. Under the repeated micro earthquakes, the vertical tension cracks at the trailing edge of the bedding slope gradually extend and connect with substratum, and the slope is mainly caused by the overall slip instability along the joint surface. Block caving firstly appears at the slope shoulder and the slope surface in the toppling slope, subsequently, the upper strata are peeled off layer by layer, and finally a circular failure surface is formed. The main characteristics of the slope are rock fall at the slope shoulder and collapse of the middle and upper strata.
The high-frequency and micro earthquake induced by the Three Gorges Reservoir after impoundment will have an important influence on the stability of the regional geological body to a certain extent. The shaking table tests and UDEC numerical analysis method are used to analyze the dynamic stability of the typical bedding and toppling rock slopes under repeated micro earthquakes. The results show that the acceleration response of the two types of slopes exhibits the "elevation effect" and "surface effect", and with the increase of earthquake action frequency, the slope damage(manifested as the initiation, expansion and penetration of structural plane and secondary rock joint) accumulates continuously and the dynamic response of the two types of slopes decreases. Under the repeated micro earthquakes, the decrease of the natural frequency of the slopes and the increase of the damping ratio are the basic laws of the dynamic characteristics. The permanent displacement increases with the increase of earthquake action frequency, and the stability coefficient decreases. Under the repeated micro earthquakes, the vertical tension cracks at the trailing edge of the bedding slope gradually extend and connect with substratum, and the slope is mainly caused by the overall slip instability along the joint surface. Block caving firstly appears at the slope shoulder and the slope surface in the toppling slope, subsequently, the upper strata are peeled off layer by layer, and finally a circular failure surface is formed. The main characteristics of the slope are rock fall at the slope shoulder and collapse of the middle and upper strata.
引文
[1]文海家,张永兴,柳源.三峡库区地质灾害及其危害[J].重庆建筑大学学报,2004,26(1):1–4.(WEN Hai-jia,ZHANG Yong-xing,LIU Yuan.Geological disasters and their damage in three gorges reservoir area[J].Journal of Chongqing Architecture University,2004,26(1):1–4.(in Chinese))
[2]王儒述.三峡水库与诱发地震[J].国际地震动态,2007(3):12–21.(WANG Ru-shu.The three gorges reservoir and induced earthquake[J].Recent Developments in World Seismology,2007(3):12–21.(in Chinese))
[3]孟庆筱,冯光钰,梅启双,等.三峡库首区非构造型水库地震的烈度衰减[J].西北地震学报,2011,33(增刊1):434–437.(MENG Qing-xiao,FENG Guang-yu,MEI Qi-shuang,et al.Intensity attenuation of non-tectonic reservoir earthquake in the head region of three gorge reservoir[J].Northwestern Seismological Journal,2011,33(S1):434–437.(in Chinese))
[4]SHIMIZU Y,AYDAN?,ICHIKAWA Y,et al.A model study on dynamic failure modes of discontinuous rock slopes[C]//Proceedings of the International Symposium on Engineering in Complex Rock Formations.1988:183–189.
[5]WANG S J,ZHANG J M.On the dynamic stability of block sliding on rock slopes[C]//Proc of the Int Cont on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics.Louis,1987:431–434.
[6]门玉明,彭建兵,李寻昌,等.层状结构岩质边坡动力稳定性试验研究[J].世界地震工程,2004,20(4):131–136.(MEN Yu-ming,PENG Jian-bing,LI Xun-chang,et al.Research on vibration testing of models for dynamic stability of rock slope with layered structures[J].World Information On Earthquake Engineering,2004,20(4):131–136.(in Chinese))
[7]王勇智,戚炜,门玉明,等.强震区岩体动力破坏机制研究[J].岩土力学,2005,26(11):1841–1844.(WANG Yong-zhi,QI Wei,MEN Yu-ming,et al.Experimental research of dynamic failure mechanism of rockmass in meizoseismal area[J].Rock and Soil Mechanics,2005,26(11):1841–1844.(in Chinese))
[8]董金玉,杨国香,伍法权,等.地震作用下顺层岩质边坡动力响应和破坏模式大型振动台试验研究[J].岩土力学,2011,32(10):2977–2982.(DONG Jin-yu,YANG Guo-xinag,WU Fa-quan,et al.The large-scale shaking table test study of dynamic response and failure mode of bedding rock slope under earthquake[J].Rock and Soil Mechanics,2011,32(10):2977–2982.(in Chinese))
[9]杨国香,伍法权,董金玉,等.地震作用下岩质边坡动力响应特性及变形破坏机制研究[J].岩石力学与工程学报,2012,31(4):696–702.(YANG Guo-xinag,WU Fa-quan,DONG Jin-yu,et al.Study of dynamic response characters and failure mechanism of rock slope under earthquake[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(4):696–702.(in Chinese))
[10]刘汉香.基于振动台试验的岩质斜坡地震动力响应规律研究[D].成都:成都理工大学,2014.(LIU Han-xiang.Seismic responses of rock slopes in a shaking table test[D].Chengdu:Chengdu University of Technology,2014.(in Chinese))
[11]叶海林,郑颖人,李安洪,等.地震作用下边坡抗滑桩振动台试验研究[J].岩土工程学报,2012,34(2):251–257.(YE Hai-lin,ZHENG Ying-ren,LI An-hong,et al.Shaking table tests on stabilizing piles of slopes under earthquakes[J].Chinese Journal of Geotechnical Engineering,2012,34(2):251–257.(in Chinese))
[12]叶海林,郑颖人,杜修力,等.边坡动力破坏特征的振动台模型试验与数值分析[J].土木工程学报,2012,45(9):128–135.(YE Hai-lin,ZHENG Ying-ren,DU Xiu-li,et al.Shaking table model test and numerical analysis on dynamic failure characteristics of slope[J].China Civil Engineering Journal,2012,45(9):128–135.(in Chinese))
[13]江洎洧.频发微震作用下三峡库首段典型滑坡变形机制及动力响应研究[D].北京:中国地质大学,2012.(JIANG Ji-wei.Research on the deformation mechanism and dynamic response of typical landslides in three gorges reservoir in case of frequent microseisms[D].Beijing:China University of Geosciences,2012.(in Chinese))
[14]李兴旺.频发微震作用下顺层岩质边坡的稳定性研究[D].重庆:重庆大学,2015.(LI Xing-wang.The analysis of the stability of beddingslope under the effect of frequent seismic[D].Chongqing:Chongqing University,2015.(in Chinese))
[15]杨兵,孙明祥,王润民,等.土体含水率对边坡动力破坏模式及动力响应影响的振动台试验研究[J].岩土工程学报,2018,40(4):759–767.(YANG Bing,SUN Ming-xiang,YANG Tao,et al.Shaking table test on influence of water content of soil on dynamic failure mode and dynamic response of slope[J].Chinese Journal of Rock Mechanics and Engineering,2018,40(4):759–767.(in Chinese))
[16]水利水电科学研究院.岩石力学参数手册[M].北京:水利电力出版社,1991.(Science China Institute of Water Resources and Hydropower Rese.Handbook of rock mechanics parameters[M].Beijing:Water Conservancy and Electric Power Press,1991.(in Chinese))
[2]王儒述.三峡水库与诱发地震[J].国际地震动态,2007(3):12–21.(WANG Ru-shu.The three gorges reservoir and induced earthquake[J].Recent Developments in World Seismology,2007(3):12–21.(in Chinese))
[3]孟庆筱,冯光钰,梅启双,等.三峡库首区非构造型水库地震的烈度衰减[J].西北地震学报,2011,33(增刊1):434–437.(MENG Qing-xiao,FENG Guang-yu,MEI Qi-shuang,et al.Intensity attenuation of non-tectonic reservoir earthquake in the head region of three gorge reservoir[J].Northwestern Seismological Journal,2011,33(S1):434–437.(in Chinese))
[4]SHIMIZU Y,AYDAN?,ICHIKAWA Y,et al.A model study on dynamic failure modes of discontinuous rock slopes[C]//Proceedings of the International Symposium on Engineering in Complex Rock Formations.1988:183–189.
[5]WANG S J,ZHANG J M.On the dynamic stability of block sliding on rock slopes[C]//Proc of the Int Cont on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics.Louis,1987:431–434.
[6]门玉明,彭建兵,李寻昌,等.层状结构岩质边坡动力稳定性试验研究[J].世界地震工程,2004,20(4):131–136.(MEN Yu-ming,PENG Jian-bing,LI Xun-chang,et al.Research on vibration testing of models for dynamic stability of rock slope with layered structures[J].World Information On Earthquake Engineering,2004,20(4):131–136.(in Chinese))
[7]王勇智,戚炜,门玉明,等.强震区岩体动力破坏机制研究[J].岩土力学,2005,26(11):1841–1844.(WANG Yong-zhi,QI Wei,MEN Yu-ming,et al.Experimental research of dynamic failure mechanism of rockmass in meizoseismal area[J].Rock and Soil Mechanics,2005,26(11):1841–1844.(in Chinese))
[8]董金玉,杨国香,伍法权,等.地震作用下顺层岩质边坡动力响应和破坏模式大型振动台试验研究[J].岩土力学,2011,32(10):2977–2982.(DONG Jin-yu,YANG Guo-xinag,WU Fa-quan,et al.The large-scale shaking table test study of dynamic response and failure mode of bedding rock slope under earthquake[J].Rock and Soil Mechanics,2011,32(10):2977–2982.(in Chinese))
[9]杨国香,伍法权,董金玉,等.地震作用下岩质边坡动力响应特性及变形破坏机制研究[J].岩石力学与工程学报,2012,31(4):696–702.(YANG Guo-xinag,WU Fa-quan,DONG Jin-yu,et al.Study of dynamic response characters and failure mechanism of rock slope under earthquake[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(4):696–702.(in Chinese))
[10]刘汉香.基于振动台试验的岩质斜坡地震动力响应规律研究[D].成都:成都理工大学,2014.(LIU Han-xiang.Seismic responses of rock slopes in a shaking table test[D].Chengdu:Chengdu University of Technology,2014.(in Chinese))
[11]叶海林,郑颖人,李安洪,等.地震作用下边坡抗滑桩振动台试验研究[J].岩土工程学报,2012,34(2):251–257.(YE Hai-lin,ZHENG Ying-ren,LI An-hong,et al.Shaking table tests on stabilizing piles of slopes under earthquakes[J].Chinese Journal of Geotechnical Engineering,2012,34(2):251–257.(in Chinese))
[12]叶海林,郑颖人,杜修力,等.边坡动力破坏特征的振动台模型试验与数值分析[J].土木工程学报,2012,45(9):128–135.(YE Hai-lin,ZHENG Ying-ren,DU Xiu-li,et al.Shaking table model test and numerical analysis on dynamic failure characteristics of slope[J].China Civil Engineering Journal,2012,45(9):128–135.(in Chinese))
[13]江洎洧.频发微震作用下三峡库首段典型滑坡变形机制及动力响应研究[D].北京:中国地质大学,2012.(JIANG Ji-wei.Research on the deformation mechanism and dynamic response of typical landslides in three gorges reservoir in case of frequent microseisms[D].Beijing:China University of Geosciences,2012.(in Chinese))
[14]李兴旺.频发微震作用下顺层岩质边坡的稳定性研究[D].重庆:重庆大学,2015.(LI Xing-wang.The analysis of the stability of beddingslope under the effect of frequent seismic[D].Chongqing:Chongqing University,2015.(in Chinese))
[15]杨兵,孙明祥,王润民,等.土体含水率对边坡动力破坏模式及动力响应影响的振动台试验研究[J].岩土工程学报,2018,40(4):759–767.(YANG Bing,SUN Ming-xiang,YANG Tao,et al.Shaking table test on influence of water content of soil on dynamic failure mode and dynamic response of slope[J].Chinese Journal of Rock Mechanics and Engineering,2018,40(4):759–767.(in Chinese))
[16]水利水电科学研究院.岩石力学参数手册[M].北京:水利电力出版社,1991.(Science China Institute of Water Resources and Hydropower Rese.Handbook of rock mechanics parameters[M].Beijing:Water Conservancy and Electric Power Press,1991.(in Chinese))
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