基于二维有限单元法的芦山M7.0地震近场强地面运动模拟
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摘要
基于2013年芦山M7.0地震近场区域深反射剖面和P波、S波层析成像资料,使用接触单元模拟断层非线性破裂过程,利用二维有限元法模拟芦山地震强地面运动。在信度检验的基础上研究震源应力降和粘聚力参数对于水平向基岩地震动参数的影响。研究发现,芦山地震上盘场址处水平地震动峰值加速度明显大于下盘场址处结果,且衰减速度更慢,呈现上下盘效应特征;应力降和粘聚力对地表水平向基岩地震动均具较为明显的正向影响作用,其中应力降对0.05～1.00s短周期成分作用明显,粘聚力则对1.00～6.00s中长周期成分具有显著影响。
According to the geophysical data obtained in the near field of the Lushan M7.0 earthquake in 2013,including the deep reflection profile and the result of P wave and S wave tomography,we establish the two-dimensional finite element model.The contact element is used to simulate the discontinuous behavior of the faults,and the numerical simulation results of the strong ground motion are further given.The results show that the ground motion parameters on hanging walls are larger than those on footwalls at the similar rupture distances,which we call the hanging-wall/foot-wall effects of near-fault ground motions.At the same time,the stress drop and cohesive force parameters have obvious positive effects on ground surface horizontal bedrock ground motion.The stress drop plays a significant role in the short period components in 0.05s-1.00 s,and cohesion has a significant effect on the medium and long period components of 1.00s-6.00 s.
According to the geophysical data obtained in the near field of the Lushan M7.0 earthquake in 2013,including the deep reflection profile and the result of P wave and S wave tomography,we establish the two-dimensional finite element model.The contact element is used to simulate the discontinuous behavior of the faults,and the numerical simulation results of the strong ground motion are further given.The results show that the ground motion parameters on hanging walls are larger than those on footwalls at the similar rupture distances,which we call the hanging-wall/foot-wall effects of near-fault ground motions.At the same time,the stress drop and cohesive force parameters have obvious positive effects on ground surface horizontal bedrock ground motion.The stress drop plays a significant role in the short period components in 0.05s-1.00 s,and cohesion has a significant effect on the medium and long period components of 1.00s-6.00 s.
引文
[1]刘杰,易桂喜,张致伟,等.2013-04-20四川芦山M7.0地震介绍[J].地球物理学报,2013,56(4):1 404-1 407(Liu Jie,Yi Guixi,Zhang Zhiwei,et al.Introduction to the Lushan,Sichuan M7.0Earthquake on 20 April 2013[J].Chinese Journal of Geophysics,2013,56(4):1 404-1 407)
[2]白玉柱,徐锡伟,李铁明,等.由强震动数据分析芦山地震地面运动持时及周期特征[J].地震地质,2017,39(1):92-103(Bai Yuzhu,Xu Xiwei,Li Tieming,et al.Spectrum Characteristics of Strong Ground Motion during the Lushan Earthquake and Correlation Analysis of the Resulting Disaster[J].Seismology and Geology,2017,39(1):92-103)
[3]喻畑,赵亚敏,陆鸣.芦山地震地震动上下盘效应研究[J].震灾防御技术,2014,9(3):431-438(Yu Tian,Zhao Yamin,Lu Ming.Study of Hanging-Wall Effect of Fault in Lushan Earthquake[J].Technology for Earthquake Disaster Prevention,2014,9(3):431-438)
[4]孟令媛,周龙泉,刘杰.2013年四川芦山MS7.0地震近断层强地面运动模拟及烈度分布估计[J].地球物理学报,2014,57(2):441-448(Meng Lingyuan,Zhou Longquan,Liu Jie.Estimation of the Near-Fault Strong Ground Motion and Intensity Distribution of the 2013Lushan,Sichuan,Ms7.0Earthquake[J].Chinese Journal of Geophysics,2014,57(2):441-448)
[5]Pacific Earthquake Engineering Research Center.Users Manual for the PEER Ground Motion Database Web Application.Beta Version[M].2010
[6]Toki K,Miura F.Simulation of a Fault Rupture Mechanism by a Two-Dimensional Finite Element Method[J].Journal of Physics of the Earth,1985,33:485-511
[7]Goodman R E.Methods of Geological Engineering in Discontinuous Rocks[M].New York:West Publishing Company,1976
[8]刘晶波,谷音,杜义欣.一致粘弹性人工边界及粘弹性边界单元[J].岩土工程学报,2006,28(9):1 070-1 075(Liu Jingbo,Gu Yin,Du Yixin.Consistent Viscous-Spring Artificial Boundaries and Viscous-Spring Boundary Elements[J].Chinese Journal of Geotechnical Engineering,2006,28(9):1 070-1 075)
[9]王夫运,赵成彬,酆少英,等.深反射剖面揭示的芦山7.0级地震发震构造[J].地球物理学报,2015,58(9):3 183-3 192(Wang Fuyun,Zhao Chengbin,Feng Shaoying,et al.Seismogenic Structure of the 2013Lushan Ms7.0Earthquake Revealed by a Deep Seismic Reflection Profile[J].Chinese Journal of Geophysics,2015,58(9):3 183-3 192)
[10]郑勇,葛粲,谢祖军,等.芦山与汶川地震震区地壳上地幔结构及深部孕震环境[J].中国科学:地球科学,2013,43(6):1 027-1 037(Zheng Yong,Ge Can,Xie Zujun,et al.Crustal and Upper Mantle Structure and the Deep Seismogenic Environment in the Source Regions of the Lushan Earthquake and the Wenchuan Earthquake[J].Science China Earth Sciences,2013,43(6):1 027-1 037)
[11]李志伟,胥颐,黄润秋,等.龙门山地区的P波速度结构与汶川地震的深部构造特征[J].中国科学:地球科学,2011,41(3):283-290(Li Zhiwei,Xu Yi,Huang Runqiu,et al.Crustal P-Wave Velocity Structure of the Longmenshan Region and Its Tectonic Implications for the 2008 Wenchuan Earthquake[J].Science China Earth Sciences,2011,41(3):283-290)
[12]陈顒,黄庭芳.岩石物理学[M].合肥:中国科学技术大学出版社,2009(Chen Yong,Huang Tingfang.Rock Physics[M].Hefei:Press of University of Science and Technology of China,2009)
[13]雷显权,陈运平,赵炯洋.天山现今地壳变形的非连续接触模型模拟[J].中南大学学报:自然科学版,2011,42(9):2 754-2 762(Lei Xianquan,Chen Yunping,Zhao Jiongyang.Discontinuous Contact Model to Simulate Current Crustal Deformation in Tianshan Mountain[J].Journal of Central South University:Science and Technology,2011,42(9):2 754-2 762)
[14]Campbell K W,Bozorgnia Y.NGA Ground Motion Model for the Geometric Mean Horizontal Component of PGA,PGV,PGD and 5%Damped Linear Elastic Response Spectra for Periods Ranging from 0.01to 10s[J].Earthquake Spectra,2008,24(1):139-171
[15]张磊,刘耀炜,任宏微,等.氢氧稳定同位素在地下水异常核实中的应用[J].地震地质,2016,38(3):721-731(Zhang Lei,Liu Yaowei,Ren Hongwei,et al.Application of Stable Oxygen and Hydrogen Isotopes to the Verification of Groundwater Anomalies[J].Seismology and Geology,2016,38(3):721-731)
[2]白玉柱,徐锡伟,李铁明,等.由强震动数据分析芦山地震地面运动持时及周期特征[J].地震地质,2017,39(1):92-103(Bai Yuzhu,Xu Xiwei,Li Tieming,et al.Spectrum Characteristics of Strong Ground Motion during the Lushan Earthquake and Correlation Analysis of the Resulting Disaster[J].Seismology and Geology,2017,39(1):92-103)
[3]喻畑,赵亚敏,陆鸣.芦山地震地震动上下盘效应研究[J].震灾防御技术,2014,9(3):431-438(Yu Tian,Zhao Yamin,Lu Ming.Study of Hanging-Wall Effect of Fault in Lushan Earthquake[J].Technology for Earthquake Disaster Prevention,2014,9(3):431-438)
[4]孟令媛,周龙泉,刘杰.2013年四川芦山MS7.0地震近断层强地面运动模拟及烈度分布估计[J].地球物理学报,2014,57(2):441-448(Meng Lingyuan,Zhou Longquan,Liu Jie.Estimation of the Near-Fault Strong Ground Motion and Intensity Distribution of the 2013Lushan,Sichuan,Ms7.0Earthquake[J].Chinese Journal of Geophysics,2014,57(2):441-448)
[5]Pacific Earthquake Engineering Research Center.Users Manual for the PEER Ground Motion Database Web Application.Beta Version[M].2010
[6]Toki K,Miura F.Simulation of a Fault Rupture Mechanism by a Two-Dimensional Finite Element Method[J].Journal of Physics of the Earth,1985,33:485-511
[7]Goodman R E.Methods of Geological Engineering in Discontinuous Rocks[M].New York:West Publishing Company,1976
[8]刘晶波,谷音,杜义欣.一致粘弹性人工边界及粘弹性边界单元[J].岩土工程学报,2006,28(9):1 070-1 075(Liu Jingbo,Gu Yin,Du Yixin.Consistent Viscous-Spring Artificial Boundaries and Viscous-Spring Boundary Elements[J].Chinese Journal of Geotechnical Engineering,2006,28(9):1 070-1 075)
[9]王夫运,赵成彬,酆少英,等.深反射剖面揭示的芦山7.0级地震发震构造[J].地球物理学报,2015,58(9):3 183-3 192(Wang Fuyun,Zhao Chengbin,Feng Shaoying,et al.Seismogenic Structure of the 2013Lushan Ms7.0Earthquake Revealed by a Deep Seismic Reflection Profile[J].Chinese Journal of Geophysics,2015,58(9):3 183-3 192)
[10]郑勇,葛粲,谢祖军,等.芦山与汶川地震震区地壳上地幔结构及深部孕震环境[J].中国科学:地球科学,2013,43(6):1 027-1 037(Zheng Yong,Ge Can,Xie Zujun,et al.Crustal and Upper Mantle Structure and the Deep Seismogenic Environment in the Source Regions of the Lushan Earthquake and the Wenchuan Earthquake[J].Science China Earth Sciences,2013,43(6):1 027-1 037)
[11]李志伟,胥颐,黄润秋,等.龙门山地区的P波速度结构与汶川地震的深部构造特征[J].中国科学:地球科学,2011,41(3):283-290(Li Zhiwei,Xu Yi,Huang Runqiu,et al.Crustal P-Wave Velocity Structure of the Longmenshan Region and Its Tectonic Implications for the 2008 Wenchuan Earthquake[J].Science China Earth Sciences,2011,41(3):283-290)
[12]陈顒,黄庭芳.岩石物理学[M].合肥:中国科学技术大学出版社,2009(Chen Yong,Huang Tingfang.Rock Physics[M].Hefei:Press of University of Science and Technology of China,2009)
[13]雷显权,陈运平,赵炯洋.天山现今地壳变形的非连续接触模型模拟[J].中南大学学报:自然科学版,2011,42(9):2 754-2 762(Lei Xianquan,Chen Yunping,Zhao Jiongyang.Discontinuous Contact Model to Simulate Current Crustal Deformation in Tianshan Mountain[J].Journal of Central South University:Science and Technology,2011,42(9):2 754-2 762)
[14]Campbell K W,Bozorgnia Y.NGA Ground Motion Model for the Geometric Mean Horizontal Component of PGA,PGV,PGD and 5%Damped Linear Elastic Response Spectra for Periods Ranging from 0.01to 10s[J].Earthquake Spectra,2008,24(1):139-171
[15]张磊,刘耀炜,任宏微,等.氢氧稳定同位素在地下水异常核实中的应用[J].地震地质,2016,38(3):721-731(Zhang Lei,Liu Yaowei,Ren Hongwei,et al.Application of Stable Oxygen and Hydrogen Isotopes to the Verification of Groundwater Anomalies[J].Seismology and Geology,2016,38(3):721-731)