地震动河谷场地效应研究
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摘要
本文以梯形河谷场地为研究对象,采用二维显式有限差分和透射人工边界理论,根据设计的正交表建立计算模型,计算分析了梯形河谷场地对地震动的影响因素,对其影响程度进行了排名,并采用强震记录分析法对计算结果进行了初步验证。结果表明,4个因素对梯形河谷场地的地表地震动有重要的影响,但是其影响程度随着位置的变化表现也不同,不同位置的影响因素排名不同;距河谷谷坡40m以内的场地,各影响因素排位相同,首位是河谷坡角,其次是深宽比、覆盖层厚度,最后是输入地震动强度,因此,河谷场地距谷坡一定距离时各因素对地表地震动影响程度基本相同,该段场地河谷地形的几何参数对地震动影响起较大作用;随着场地距河谷谷坡越远,影响因素的排位也发生了变化,总体上是坡角排位后移,输入地震动和覆盖层厚度排位前移,河谷几何参数对地震动影响逐渐减弱,覆盖层厚度和输入地震强度2个因素的影响逐渐加大,该段场地对地震动影响与水平成层场地类似。对安宁河河谷场地强震记录分析验证的结果表明,河谷地形对地震动有显著的放大作用,同时也验证了本文的数值模拟结果是可信的。
Taking the trapezoid-shaped valley as a research site, according to numerous models based on orthogonal design, we studied the factors that influence ground motion in the valley site with two-dimensional finite difference method. Factors are ranked based on their importances, then the calculation results are verified by ground motion analysis. We found that there are four factors with important effect on ground motion of trapezoid valley site, but the effects are different as the sites changed. Within a distance 40 m from river valley ranking factors of site are same. The fist factor is valley angle, the second is ratio of bottom width, the third is cover thickness, and the last one is input ground motion intensity. Therefore it is the same impact degree of factors on ground motion in some distances from the site to the slope of the valley, in which geometric parameters of the valley plays a great part in the effect on ground motion. With the further away from the valley slope, the ranking of factors have also changed, the angles of slope rating are moved back, input ground motion and cover thickness move ahead, the major factors have changed. The effect of valley geometric parameters motions are gradually weakened, but the other two factors influence is gradually increased, that is similar to levels of the layered site. Strong motion records in the Anning river valley site are analyzed as a study case, and the results show that effect of the valley topography on the ground motion is a significantly amplified, and the numerical results of this paper are credible.
Taking the trapezoid-shaped valley as a research site, according to numerous models based on orthogonal design, we studied the factors that influence ground motion in the valley site with two-dimensional finite difference method. Factors are ranked based on their importances, then the calculation results are verified by ground motion analysis. We found that there are four factors with important effect on ground motion of trapezoid valley site, but the effects are different as the sites changed. Within a distance 40 m from river valley ranking factors of site are same. The fist factor is valley angle, the second is ratio of bottom width, the third is cover thickness, and the last one is input ground motion intensity. Therefore it is the same impact degree of factors on ground motion in some distances from the site to the slope of the valley, in which geometric parameters of the valley plays a great part in the effect on ground motion. With the further away from the valley slope, the ranking of factors have also changed, the angles of slope rating are moved back, input ground motion and cover thickness move ahead, the major factors have changed. The effect of valley geometric parameters motions are gradually weakened, but the other two factors influence is gradually increased, that is similar to levels of the layered site. Strong motion records in the Anning river valley site are analyzed as a study case, and the results show that effect of the valley topography on the ground motion is a significantly amplified, and the numerical results of this paper are credible.
引文
陈云雀,何蕴龙,2013.P波倾斜入射时河谷地震动相应研究.武汉大学学报(工学版),46(6):702-710.
陈清军,张巍,夏江,2013.基于PC集群的三维河谷场地长周期地震动响应并行计算.防灾减灾工程学报,33(3):263-268.
崔江余,杜修力,2001.河谷自由场地震动经验传递函数研究.水利学报,32(10):59-62.
车伟,罗奇峰,2008.复杂地形条件下地震波的传播研究.岩土工程学报,30(9):1333-1337.
董俊,赵成刚,2005.半球形凹陷饱和土半空间对入射平面SV波三维散射问题的解析解.地球物理学报,48(6):1412-1421.
金峰,张楚汉,王光纶,1993.结构地基相互作用的FE-BE-IBE耦合模型.清华大学学报(自然科学版),33(2):17-25.
金丹丹,陈国兴,董菲蕃,2014.多地貌单元复合场地非线性地震效应特征二维分析.岩土力学,35(6):1818-1825.
廖振鹏,2002.工程波动理论导论(第二版).北京:科学出版社.
廖振鹏,杨柏坡,1986.频域透射边界.地震工程与工程振动,6(4):1-9.
廖振鹏,黄孔亮,杨柏坡等,1984.暂态波透射边界.中国科学A辑,27(6):556-564.
梁建文,张郁山,顾晓鲁等,2000.圆弧形层状沉积河谷场地在平面SH波入射下动力响应分析.岩土工程学报,22(4):396-401.
梁建文,严林隽,Lee V.W.,2001a.圆弧形凹陷地形地表覆盖层对入射平面SV波的影响.地震学报,23(6):622-636.
梁建文,严林隽,李军伟等,2001b.圆弧形沉积河谷场地在平面P波入射下的响应.岩土力学,22(2):138-143.
梁建文,严林,Lee V.W.,2002.圆弧形凹陷地形表面覆盖层对入射平面P波的影响.固体力学学报,23(4):397-411.
梁建文,张郁山,顾晓鲁等,2003.圆弧形层状凹陷地形对平面SH波的散射.振动工程学学报,16(2):158-165.
李平,2013.汶川特大地震汉源震害异常研究.哈尔滨:中国地震局工程力学研究所.
刘必灯,周正华,刘培玄等,2011.SV波入射情况下V型河谷地形对地震动的影响分析.地震工程与工程振动,31(2):17-24.
刘天云,刘光廷,2000.拱坝河谷三维地震动分析.水利学报,31(9):79-85.
曲国胜,黄建发,李小军等,张晓东,2008.南亚(巴基斯坦)地震灾害分布及成因分析.震灾防御技术,3(1):85-94.
任叶飞,温瑞智,山中浩明等,2013.运用广义反演法研究汶川地震场地效应.土木工程学报,46(增):146-151.
宋贞霞,丁海平,2013.三维不规则地形河谷场地地震响应分析方法研究.地震工程与工程振动,33(2):8-15.
肖文海,2009.大型河谷场地地震动特征研究.哈尔滨:中国地震局工程力学研究所.
王伟,2011.地震动的山体地形效应.哈尔滨:中国地震局工程力学研究所.
王海云,2011.渭河盆地中土层场地对地震动的放大作用.地球物理学报,54(1):137-150.
谢定义,陈存礼,胡再强,2011.试验土工学.北京:高等教育出版社.
张孝波,景立平,肖文海,2010.大型河谷场地地震动特性研究.防灾减灾工程学报,30(6):644-649.
张建毅,薄景山,王振宇等,2012.汶川地震局部地形对地震动的影响.自然灾害学报,21(3):164-169.
Bordoni P.,Del Monaco F.,Milana G.,et al.,2014.The seismic response at high frequency in central L’Aquila:Acomparison between spectral ratios of 2D modeling and observations of the 2009 aftershocks.Bulletin of the Seismological Society of America,104(3):1374-1388.
Frischknecht C.,Wagner J.J.,2004.Seismic soil effect in an embanked deep alpine valley:a numerical investigation of two-dimensional resonance.Bulletin of the Seismological Society of America,94(1):171-186.
Gao Y.F.,Zhang N.,Li D.Y.,et al.,2012.Effects of topographic amplification induced by a U-shaped canyon on seismic waves.Bulletin of the Seismological Society of America,102(4):1748-1763.
Lee W.H.,White R.A.,Harlow D.H.,et al.,1994.Digital seismograms of selected aftershocks of the Northridge earthquake recorded by a dense seismic array on February 11,1994 at Cedar Hill Nursery in Tarzana,California.Open-File Report 94-234.[S.l.]:U.S.Geological Survey.
Sohrabi-Bidar A.,Kamalian M.,Jafari M.K.,2010.Seismic response of 3D Gaussian-shaped valleys to vertically propagating incident waves.Geophysical Journal International,183(3):1429-1442.
Tsaur D.H.,Chang K.H.,2008.An analytical approach for the scattering of SH waves by a symmetrical V-shapedcanyon:Shallow case.Geophysical Journal International,174(1):255-264.
Wong,H.L.,Jennings P.C.,1975.Effects of canyon topography on strong ground motion.Bulletin of the Seismological Society of America,65(5):1239-1257.
Zhang N.,Gao Y.F.,Cai Y.Q.et al.,2012.Scattering of SH waves induced by a non-symmetrical V-shaped canyon.Geophysical Journal International,191(1):243-256.
陈清军,张巍,夏江,2013.基于PC集群的三维河谷场地长周期地震动响应并行计算.防灾减灾工程学报,33(3):263-268.
崔江余,杜修力,2001.河谷自由场地震动经验传递函数研究.水利学报,32(10):59-62.
车伟,罗奇峰,2008.复杂地形条件下地震波的传播研究.岩土工程学报,30(9):1333-1337.
董俊,赵成刚,2005.半球形凹陷饱和土半空间对入射平面SV波三维散射问题的解析解.地球物理学报,48(6):1412-1421.
金峰,张楚汉,王光纶,1993.结构地基相互作用的FE-BE-IBE耦合模型.清华大学学报(自然科学版),33(2):17-25.
金丹丹,陈国兴,董菲蕃,2014.多地貌单元复合场地非线性地震效应特征二维分析.岩土力学,35(6):1818-1825.
廖振鹏,2002.工程波动理论导论(第二版).北京:科学出版社.
廖振鹏,杨柏坡,1986.频域透射边界.地震工程与工程振动,6(4):1-9.
廖振鹏,黄孔亮,杨柏坡等,1984.暂态波透射边界.中国科学A辑,27(6):556-564.
梁建文,张郁山,顾晓鲁等,2000.圆弧形层状沉积河谷场地在平面SH波入射下动力响应分析.岩土工程学报,22(4):396-401.
梁建文,严林隽,Lee V.W.,2001a.圆弧形凹陷地形地表覆盖层对入射平面SV波的影响.地震学报,23(6):622-636.
梁建文,严林隽,李军伟等,2001b.圆弧形沉积河谷场地在平面P波入射下的响应.岩土力学,22(2):138-143.
梁建文,严林,Lee V.W.,2002.圆弧形凹陷地形表面覆盖层对入射平面P波的影响.固体力学学报,23(4):397-411.
梁建文,张郁山,顾晓鲁等,2003.圆弧形层状凹陷地形对平面SH波的散射.振动工程学学报,16(2):158-165.
李平,2013.汶川特大地震汉源震害异常研究.哈尔滨:中国地震局工程力学研究所.
刘必灯,周正华,刘培玄等,2011.SV波入射情况下V型河谷地形对地震动的影响分析.地震工程与工程振动,31(2):17-24.
刘天云,刘光廷,2000.拱坝河谷三维地震动分析.水利学报,31(9):79-85.
曲国胜,黄建发,李小军等,张晓东,2008.南亚(巴基斯坦)地震灾害分布及成因分析.震灾防御技术,3(1):85-94.
任叶飞,温瑞智,山中浩明等,2013.运用广义反演法研究汶川地震场地效应.土木工程学报,46(增):146-151.
宋贞霞,丁海平,2013.三维不规则地形河谷场地地震响应分析方法研究.地震工程与工程振动,33(2):8-15.
肖文海,2009.大型河谷场地地震动特征研究.哈尔滨:中国地震局工程力学研究所.
王伟,2011.地震动的山体地形效应.哈尔滨:中国地震局工程力学研究所.
王海云,2011.渭河盆地中土层场地对地震动的放大作用.地球物理学报,54(1):137-150.
谢定义,陈存礼,胡再强,2011.试验土工学.北京:高等教育出版社.
张孝波,景立平,肖文海,2010.大型河谷场地地震动特性研究.防灾减灾工程学报,30(6):644-649.
张建毅,薄景山,王振宇等,2012.汶川地震局部地形对地震动的影响.自然灾害学报,21(3):164-169.
Bordoni P.,Del Monaco F.,Milana G.,et al.,2014.The seismic response at high frequency in central L’Aquila:Acomparison between spectral ratios of 2D modeling and observations of the 2009 aftershocks.Bulletin of the Seismological Society of America,104(3):1374-1388.
Frischknecht C.,Wagner J.J.,2004.Seismic soil effect in an embanked deep alpine valley:a numerical investigation of two-dimensional resonance.Bulletin of the Seismological Society of America,94(1):171-186.
Gao Y.F.,Zhang N.,Li D.Y.,et al.,2012.Effects of topographic amplification induced by a U-shaped canyon on seismic waves.Bulletin of the Seismological Society of America,102(4):1748-1763.
Lee W.H.,White R.A.,Harlow D.H.,et al.,1994.Digital seismograms of selected aftershocks of the Northridge earthquake recorded by a dense seismic array on February 11,1994 at Cedar Hill Nursery in Tarzana,California.Open-File Report 94-234.[S.l.]:U.S.Geological Survey.
Sohrabi-Bidar A.,Kamalian M.,Jafari M.K.,2010.Seismic response of 3D Gaussian-shaped valleys to vertically propagating incident waves.Geophysical Journal International,183(3):1429-1442.
Tsaur D.H.,Chang K.H.,2008.An analytical approach for the scattering of SH waves by a symmetrical V-shapedcanyon:Shallow case.Geophysical Journal International,174(1):255-264.
Wong,H.L.,Jennings P.C.,1975.Effects of canyon topography on strong ground motion.Bulletin of the Seismological Society of America,65(5):1239-1257.
Zhang N.,Gao Y.F.,Cai Y.Q.et al.,2012.Scattering of SH waves induced by a non-symmetrical V-shaped canyon.Geophysical Journal International,191(1):243-256.