考虑地震波斜入射下河谷地形的大跨桥梁动力反应研究
|
摘要
大跨度桥梁的地震动空间变化的非一致影响不可忽略,斜入射是引起这种空间变化的主要因素.研究了斜入射条件下自由场数值模拟方法,建立了考虑地震动空间非一致性的大跨度桥梁三维有限元分析模型,以某跨海连续刚构桥为背景,研究了考虑非一致地震动空间的大跨桥梁地震动力反应,分析桥梁的内力幅值和分布规律.研究了地震波输入、斜入射角、地基土剪切波速以及河谷地形等影响因素的变化对P波及SV波作用下连续刚构桥结构动力反应的影响规律.结果表明,河谷地形条件下,墩底内力的变形规律和平坦地形相比有一些差异.斜入射时河谷地形的剪力和轴力的非一致影响系数与平坦地形相差比较大,P波作用下,墩底剪力和纵桥向弯矩随着入射角的增大而增大,墩底轴力随着入射角的增大而减小,SV波入射时,河谷地形条件下的墩底剪力和纵桥向弯矩随着入射角的增大而减小,墩底轴力随着入射角的增大而增大.
The non-uniform effects of long-span bridges under spatial variation of ground motions can not be neglected.Oblique incidence plays a vital role in triggering such spatial variation.The numerical simulation method of free field under oblique incidence is studied.A three-dimensional FEA model considering the spatially non-uniform ground motion is built to analyze the seismic responses of a certain continuous rigid-frame bridge with large span.On the background of a crossing sea continuous rigid frame bridge,the seismic analysis of long-span bridge is presented and the amplitude and distribution of internal forces are studied.When influencing factors like seismic wave input,oblique incident angle and shear wave velocity of the soil are changing,the dynamic response influencing laws of continuous rigid frame bridges under P-wave and SV-wave are summarized.
The non-uniform effects of long-span bridges under spatial variation of ground motions can not be neglected.Oblique incidence plays a vital role in triggering such spatial variation.The numerical simulation method of free field under oblique incidence is studied.A three-dimensional FEA model considering the spatially non-uniform ground motion is built to analyze the seismic responses of a certain continuous rigid-frame bridge with large span.On the background of a crossing sea continuous rigid frame bridge,the seismic analysis of long-span bridge is presented and the amplitude and distribution of internal forces are studied.When influencing factors like seismic wave input,oblique incident angle and shear wave velocity of the soil are changing,the dynamic response influencing laws of continuous rigid frame bridges under P-wave and SV-wave are summarized.
引文
[1]刘必灯,周正华,刘培玄,等.SV波入射情况下V型河谷地形对地震动的影响分析[J].地震工程与工程振动,2011,31(2):17-25.
[2]周国良.河谷地形对多支撑大跨桥梁地震反应影响[D].哈尔滨:中国地震局工程力学研究所,2010.
[3]Trifunac M D.Scattering of plane SH waves by a semicylindrical canyon[J].Earthquake Engineering and Structural Dynamics,1973,1(3):267-281.
[4]Eurocode 8,Structures in seismic regions design,Part 2,bridges[S].draft.Brussels European Committee for Standardizan-tion,1995.
[5]中华人们共和国交通运输部.JTG/TB 02-01-2008公路桥梁抗震设计细则[S].北京:人民交通出版社,2008.
[6]刘琳.考虑地形效应下桥梁随机振动分析[D].北京:北京工业大学,2005.
[7]Nazm y A S,Abdel-Ghaffar A M.Effect of ground motion spatial variability on the response of cable-stayed bridges[J].Earthquake Engineering and Structural Dynamics,1992,21(1):1-20.
[8]Zhang Jian,Makris N.Seismic respolkse analysis of highway overcrossings including soil-structure interaction[R].Berkeley:University of California,2001.
[9]孙利民,孙晨南,潘龙,等.桥梁桩土相互作用的集中质量模型及参数确定[J].同济大学学报,2002,30(4):409-415.
[10]谷音,刘晶波,杜义欣.三维一致粘弹性人工边界及等效粘弹性边界单元[J].工程力学,2007,24(12):31-38
[11]王艳.非一致地震动场数值方法研究及在结构动力分析中的应用[D].北京:清华大学,2007.
[12]Prakash V,Powell G H,Campbell S.DRA IN22DX base program description and user guide[R].Berkeley:University ofCalifornia,1993.
[2]周国良.河谷地形对多支撑大跨桥梁地震反应影响[D].哈尔滨:中国地震局工程力学研究所,2010.
[3]Trifunac M D.Scattering of plane SH waves by a semicylindrical canyon[J].Earthquake Engineering and Structural Dynamics,1973,1(3):267-281.
[4]Eurocode 8,Structures in seismic regions design,Part 2,bridges[S].draft.Brussels European Committee for Standardizan-tion,1995.
[5]中华人们共和国交通运输部.JTG/TB 02-01-2008公路桥梁抗震设计细则[S].北京:人民交通出版社,2008.
[6]刘琳.考虑地形效应下桥梁随机振动分析[D].北京:北京工业大学,2005.
[7]Nazm y A S,Abdel-Ghaffar A M.Effect of ground motion spatial variability on the response of cable-stayed bridges[J].Earthquake Engineering and Structural Dynamics,1992,21(1):1-20.
[8]Zhang Jian,Makris N.Seismic respolkse analysis of highway overcrossings including soil-structure interaction[R].Berkeley:University of California,2001.
[9]孙利民,孙晨南,潘龙,等.桥梁桩土相互作用的集中质量模型及参数确定[J].同济大学学报,2002,30(4):409-415.
[10]谷音,刘晶波,杜义欣.三维一致粘弹性人工边界及等效粘弹性边界单元[J].工程力学,2007,24(12):31-38
[11]王艳.非一致地震动场数值方法研究及在结构动力分析中的应用[D].北京:清华大学,2007.
[12]Prakash V,Powell G H,Campbell S.DRA IN22DX base program description and user guide[R].Berkeley:University ofCalifornia,1993.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心