基于地表地震输入的深基础结构地震反应分析
|
摘要
桩基是一种历史悠久、且广泛采用的深基础形式,历次大地震中,均出现了各类桩基础的严重破坏现象。由于破坏的隐蔽性,使得破坏桩基的修复极为困难而且耗资巨大,因此,对地震作用下土-桩-结构动力相互作用进行数值分析具有重要的学术意义和较强的工程实用价值。
本文在研读大量国内外文献的基础上,对前人的成果按地震波的反演分析、桩的分析模型、土-桩-结构动力相互作用的分析方法等几个方面进行了系统地分析和总结,并按下述思路开展了本文的研究工作:
(1)推导了线粘弹性土体中垂直入射的剪切波的水平位移方程,根据波动理论,对地表地震加速度记录进行反演分析计算,得到地层某深度处(或基岩处)的地震加速度。结论表明,经过反演,地震波形没有根本性的变化,但土层对地震波的放大作用是很明显的;基岩深度不同,对加速度的影响亦不同,加速度最大幅值放大系数一般随基岩深度的增加而增加。
(2)以动力Winkler地基上的梁模型为基础,以单调加载得到的单桩p-y曲线为骨干曲线,用修正的Ramberg-Osgood模型建立单桩在不规则循环荷载作用下的p-y曲线,从而可以方便地确定不规则循环荷载作用下土体的水平刚度,模拟土体的非线性,并考虑土体的材料和滞回阻尼特性,结合有限元思想建立土-桩-结构体系动力相互作用的控制方程,编制相应的计算程序。运用该模型对单桩支承的剪切性结构体系进行了较全面的参数分析。
(3)基于Penzien提出的集中质量模型,将上部结构和桩基础离散为剪切型质点串,以弹簧和阻尼器模拟桩周围的土体,考虑了等价土体层间剪切和阻尼效应,给出了相互作用参数的确定方法,建立土-桩-结构动力相互作用的简化分析模型,通过对土体模量的等价线性迭代逼近体系的非线性动力响应。将该分析模型退化运用到单桩情况,并与前面单桩简化分析的结果进行比较,结果表明两种模型吻合较好。通过运用该模型对高柔结构以及相对刚性结构进行地震响应时程分析得出:对于高柔结构而言,相互作用对体系地震响应的影响不太显著,对相对刚性的结构则有显著的影响。
Pile foundation has been used to consolidate soft ground for a long history, and it is also one popular means to be used to improve foundation today. Many pile foundations are damaged seriously during the past major earthquakes. Large amount of cost will be paid to remedy the defect of pile foundation undergoing earthquakes, so it is a significant value for both academic and concrete project to study the subject of numerical analysis of Soil-Pile-Structure Dynamic Interaction under seismic loading. Based on the review of past research work, a state-of-art with respect to Soil-Pile-Structure Dynamic Interaction, which includes inversion analysis, pile analysis models, analysis methods, is presented and analyzed firstly. Research work is conducted in light of the processes as follows:
(1) The paper formulates horizontal displacement equation of upright shear wave in linear visco-elastic soil which is assumed to be horizontally layered, and makes an inversion analysis in frequency domain based on wave theory. Fourier transform is applied to transform the earthquake acceleration records measured from the ground surface from time domain to frequency domain and the earthquake acceleration records are made inversion computation in frequency domain, and the earthquake accelerations of any soil layer (or bed rock) below ground surface are gotten. Results indicate that, when the seismic wave passes through the soil layers, the wave shape don’t change basically, but the amplificatory effect on seismic wave of soil layer is evident. The effect on acceleration is different with the change of depth of rock. And the maximal value of acceleration will increase with the augmentation of depth of bed rock.
(2) To model nonlinearity and hysteretic character of soil under seismic loading, the p-y curve of single pile under monotonic loading is used as the skeleton curve and modified Ramberg-Osgood model theory is employed to construct the hysteretic loop for single pile dynamic p-y curve. The improved model is used in the Dynamic Beam on Nonlinear Winkler Foundation method. Both material and hysteretic damping of soil are taken into consideration. The governing equation of motion is set up combining with theory of FEM, and a computation program is written based on above theory. A comprehensive parametric study is also done for shear type structure supported by a
本文在研读大量国内外文献的基础上,对前人的成果按地震波的反演分析、桩的分析模型、土-桩-结构动力相互作用的分析方法等几个方面进行了系统地分析和总结,并按下述思路开展了本文的研究工作:
(1)推导了线粘弹性土体中垂直入射的剪切波的水平位移方程,根据波动理论,对地表地震加速度记录进行反演分析计算,得到地层某深度处(或基岩处)的地震加速度。结论表明,经过反演,地震波形没有根本性的变化,但土层对地震波的放大作用是很明显的;基岩深度不同,对加速度的影响亦不同,加速度最大幅值放大系数一般随基岩深度的增加而增加。
(2)以动力Winkler地基上的梁模型为基础,以单调加载得到的单桩p-y曲线为骨干曲线,用修正的Ramberg-Osgood模型建立单桩在不规则循环荷载作用下的p-y曲线,从而可以方便地确定不规则循环荷载作用下土体的水平刚度,模拟土体的非线性,并考虑土体的材料和滞回阻尼特性,结合有限元思想建立土-桩-结构体系动力相互作用的控制方程,编制相应的计算程序。运用该模型对单桩支承的剪切性结构体系进行了较全面的参数分析。
(3)基于Penzien提出的集中质量模型,将上部结构和桩基础离散为剪切型质点串,以弹簧和阻尼器模拟桩周围的土体,考虑了等价土体层间剪切和阻尼效应,给出了相互作用参数的确定方法,建立土-桩-结构动力相互作用的简化分析模型,通过对土体模量的等价线性迭代逼近体系的非线性动力响应。将该分析模型退化运用到单桩情况,并与前面单桩简化分析的结果进行比较,结果表明两种模型吻合较好。通过运用该模型对高柔结构以及相对刚性结构进行地震响应时程分析得出:对于高柔结构而言,相互作用对体系地震响应的影响不太显著,对相对刚性的结构则有显著的影响。
Pile foundation has been used to consolidate soft ground for a long history, and it is also one popular means to be used to improve foundation today. Many pile foundations are damaged seriously during the past major earthquakes. Large amount of cost will be paid to remedy the defect of pile foundation undergoing earthquakes, so it is a significant value for both academic and concrete project to study the subject of numerical analysis of Soil-Pile-Structure Dynamic Interaction under seismic loading. Based on the review of past research work, a state-of-art with respect to Soil-Pile-Structure Dynamic Interaction, which includes inversion analysis, pile analysis models, analysis methods, is presented and analyzed firstly. Research work is conducted in light of the processes as follows:
(1) The paper formulates horizontal displacement equation of upright shear wave in linear visco-elastic soil which is assumed to be horizontally layered, and makes an inversion analysis in frequency domain based on wave theory. Fourier transform is applied to transform the earthquake acceleration records measured from the ground surface from time domain to frequency domain and the earthquake acceleration records are made inversion computation in frequency domain, and the earthquake accelerations of any soil layer (or bed rock) below ground surface are gotten. Results indicate that, when the seismic wave passes through the soil layers, the wave shape don’t change basically, but the amplificatory effect on seismic wave of soil layer is evident. The effect on acceleration is different with the change of depth of rock. And the maximal value of acceleration will increase with the augmentation of depth of bed rock.
(2) To model nonlinearity and hysteretic character of soil under seismic loading, the p-y curve of single pile under monotonic loading is used as the skeleton curve and modified Ramberg-Osgood model theory is employed to construct the hysteretic loop for single pile dynamic p-y curve. The improved model is used in the Dynamic Beam on Nonlinear Winkler Foundation method. Both material and hysteretic damping of soil are taken into consideration. The governing equation of motion is set up combining with theory of FEM, and a computation program is written based on above theory. A comprehensive parametric study is also done for shear type structure supported by a
引文
[1] P.J. Meymand. Shaking Table Scale Model Tests of Nonlinear Soil-Pile-Structure Interaction in Soft Clay[D]. University of California, Berkeley, 1998.
[2] Lok,M. Numerical Modeling of Seismic Soil-Pile-Structure Interaction in Soft Clay[D]. University of California, Berkeley, 1999.
[3] 李辉,刘立平,赖明。基于地面地震反应输入的自由场地震反应分析。四川建筑科学研究,2004,30(3)。
[4] 王伟,杨尧志。地基基础与上部结构共同作用抗震性能分析[J]。武汉水利电力大学学报,2000,8,33(4),59-63。
[5] 胡聿贤。地震工程学[M]。北京:地震出版社,1988。
[6] 刘惠珊。桩基震害及原因分析-日本阪神大地震的启示[J]。工程抗震,1993,1,37-43。
[7] 庄礼贤,尹协远,马晖扬。流体力学。安徽:中国科学技术大学出版社,1991。
[8] 王松涛,曹资。现代抗震设计方法。北京:中国建筑工业出版社,1997。
[9] 徐芝纶,弹性力学简明教程。北京:高等教育出版社,1983。
[10] 庄礼贤,尹协远,马晖扬。流体力学。安徽:中国科学技术大学出版社,1991。
[11] 杨桂通,土动力学。北京:中国建材工业出版社,2000。
[12] 张建民,张嘎。土体与结构物动力相互作用的研究进展[J]。 岩石力学与工程学报, 2001, 5,20 (增1):854-865
[13] Novak,M. Dynamic Stiffness and Damping of Piles[J]. Can. Geotech. J.,1974, 11(4):574-598.
[14] Novak,M., Nogami,T. Soil-Pile Interaction in Horizontal Vibration[J]. Earthquake Engineering and Structure Dynamics, 1977, 5(3):263-281.
[15] Novak, M. Nogami, T. Aboul-Ella, F. Dynamic Soil Reaction for Plane Strain Case[J]. Journal of the Engineering Mechanics Division, ASCE, 1978, 104, EM4: 953-959.
[16] M. Novak. Piles Under Dynamic Loads[A]. Proceedings: 2th International Conference on Recent Advances in Geotecnical Earthquake Engineering and Soil Dynamics[C], March 11-15, 1991, Vol. III, St.Louis, Missouri.
[17] 林皋。土-结构动力相互作用[J]。 世界地震工程,1991,7(2):4-21。
[18] 林皋。岩土地震工程及土动力学新进展[J]。世界地工程,1992,5,2:1-11。
[19] 陈国兴.土体-结构体系的地震性能研究[J]. 哈尔滨建筑工程学院学报, 1994,10,27 (5):11-18.
[20] 肖晓春,林皋,迟世春。土-桩-结构动力相互作用的分析模型与方法[J]。世界地震工程,2002,4:123-130。
[21] 胡聿贤。地震工程学[M]。北京:地震出版社,1988。
[22] J. Peizien. Seismic Analysis of Bridges on Long Piles[J]. J. Engng. Mech. Div., ASCE, 1964, 90 (EM3):223-254.
[23] 宰金珉,宰金璋。高层建筑基础分析与设计-土与结构物共同作用的理论与应用[M]。北京:中国建筑工业出版社,1993。
[24] 周铭。弹性桩与弹性梁的通解[J]。岩土工程学报,1982,2,4(1):1-15。
[25] G.Gazetas, R.Dobry. Horizontal Response of Piles in Layered Soils[J]. Journal of Geotechnical Engineering, ASCE. 1984, 1,110(1):20-40.
[26] K.Fan, G.Gazetas. A.Kaynia. Kinematic Seismic Response of Single Piles and Pile Groups[J]. Journal of Geotechnical Engineering, ASCE, 1991, 12, 117 (12): 1860 -1879.
[27] N.Mrakis, G.Gazetas. Dynamic Pile-Soil-Pile Interaction Part II: Analysis of Lateral Vibration[J]. Earthquake Engineering and Structural Dynamics,1992,21: 145-162.
[28] 王立忠,柯瀚,陈云敏,吴世明。地震荷载作用下水泥搅拌桩的动力响应[J]。振动工程学报,1998,10,11(4):416-423。
[29] 林天剑,熊厚金,王利群。桩基础设计指南[M]。北京:中国建筑工业出版社,1999。
[30] Y.X.Cai, P.L.Gould, C.S.Desai. Evaluation of Seismic Response of Pile-Supported Structure with 3-D Nonlinear Approach[A]. Proceedings: 3th International Conference on Recent Advances in Geotecnical Earthquake Engineering and Soil Dynamic[C], 1995,Vol.III,St.Louis,Missouri, Paper No.5.45.
[31] Y.X.Cai, P.L.Gould, C.S.Desai. Nonlinear Analysis of 3D Seismic Interaction of Soil-Pile-Structure Systems and Application[J]. Engineering Structures, 2000,22,191-199.
[32] 李辉,赖明,白绍良。土-结构动力相互作用研究综述(II)[J]。重庆建筑大学学报,1999,10。
[33] Guoxi Wu, W.D.Liam Finn. Dynamic Elastic Analysis of Pile Foundations Using Finite Element Method in the Frequency Domain[J], Can. Geotech. J.1997,34: 34-43.
[34] Guoxi Wu, W.D.Liam Finn. Dynamic Nonlinear Analysis of Pile Foundations Using Finite Element Method in the Time Domain [J], Can. Geotech. J. 1997,34:44-52.
[35] W.D.Liam Finn,T Thavaraj, W D Wilson, et.al. Seismic Response Analysis of Pile Foundations at Liquefiable Sites[A], 12WCEE,2000, Paper No.0422.
[36] 刘汉龙,余湘娟。土动力学与岩土地震工程研究进展[J]。河海大学学报,1996,27(1):6-15。
[37] 刘晶波,吕彦东。结构-地基动力相互作用问题分析的一种直接方法[J]。 土木工程学报,1998,6,31(3):55-64。
[38] Poulos, H.G. and Davis, E.H. Pile Foundation Analysis and Design[M]. John Wiley and Sons, New York, 1980.
[39] 卢世深,林亚超编译。桩基础的计算与分析[M]。北京:人民交通出版社,1987。
[40] Desai C.S. Wathugala G.W. Constitutive Model for Cyclic Behavior of Clays II: Applications[J]. Journal of Geotechnical Engineering ASCE. 1993,119(4): 730– 749.
[41] G.Gazetae. et al. Seismic Response of End-Bearing Single Piles[J]. Soil Dynamics and Earthquake Engineering. 1984,3(2):82-93.
[42] J. Peizien, et al. Seismic analysis of bridges on long piles[J]. Journal of Engine. Mech. Div., ASCE, 1964,90 (EM3):223-254.
[43] 解明雨,孙焕纯。桩基础的高层建筑弹塑性地震反应分析[J]。大连工学院学报, 1983,6,22(2):9-16。
[44] 王有为,王开顺。建筑物-桩-土相互作用地震反应分析的研究[J]。建筑结构学报, 1985,5,64-73。
[45] 严士超,杜一平。电视塔-桩-土相互作用的地震反应分析[J]。土木工程学报,1991, (3): 71-79。
[46] Anagnostopoulos S. A. Pile foundation modeling for inelastic earthquake analyses of large structures [J]. Engineering Structures, 1983,5(2):15-22.
[47] 王有为,王开顺。地震作用下群桩水平刚度的计算方法及其程序设计[J]。土木工程学报, 1984, (1):39-48。
[48] GB50191-93,构筑物抗震设计规范[S]。北京:中国建筑出版社, 1993。
[49] K.J.Ahn, L.Gould. Interactive Base Isolation System: I. Finite Element Formulation [J]. Journal of Engineering Mechanics, ASCE. 1992, 10, 118 (10): 2048-2058.
[50] 钱家欢,殷宗泽。土工原理与计算[M]。北京:水利水电出版社,1994。
[51] 熊建国,王丹民,熊朝辉。考虑土-结构非线性相互作用下的结构地震反应分析[J]。建筑科学,1996,4,6-1。
[2] Lok,M. Numerical Modeling of Seismic Soil-Pile-Structure Interaction in Soft Clay[D]. University of California, Berkeley, 1999.
[3] 李辉,刘立平,赖明。基于地面地震反应输入的自由场地震反应分析。四川建筑科学研究,2004,30(3)。
[4] 王伟,杨尧志。地基基础与上部结构共同作用抗震性能分析[J]。武汉水利电力大学学报,2000,8,33(4),59-63。
[5] 胡聿贤。地震工程学[M]。北京:地震出版社,1988。
[6] 刘惠珊。桩基震害及原因分析-日本阪神大地震的启示[J]。工程抗震,1993,1,37-43。
[7] 庄礼贤,尹协远,马晖扬。流体力学。安徽:中国科学技术大学出版社,1991。
[8] 王松涛,曹资。现代抗震设计方法。北京:中国建筑工业出版社,1997。
[9] 徐芝纶,弹性力学简明教程。北京:高等教育出版社,1983。
[10] 庄礼贤,尹协远,马晖扬。流体力学。安徽:中国科学技术大学出版社,1991。
[11] 杨桂通,土动力学。北京:中国建材工业出版社,2000。
[12] 张建民,张嘎。土体与结构物动力相互作用的研究进展[J]。 岩石力学与工程学报, 2001, 5,20 (增1):854-865
[13] Novak,M. Dynamic Stiffness and Damping of Piles[J]. Can. Geotech. J.,1974, 11(4):574-598.
[14] Novak,M., Nogami,T. Soil-Pile Interaction in Horizontal Vibration[J]. Earthquake Engineering and Structure Dynamics, 1977, 5(3):263-281.
[15] Novak, M. Nogami, T. Aboul-Ella, F. Dynamic Soil Reaction for Plane Strain Case[J]. Journal of the Engineering Mechanics Division, ASCE, 1978, 104, EM4: 953-959.
[16] M. Novak. Piles Under Dynamic Loads[A]. Proceedings: 2th International Conference on Recent Advances in Geotecnical Earthquake Engineering and Soil Dynamics[C], March 11-15, 1991, Vol. III, St.Louis, Missouri.
[17] 林皋。土-结构动力相互作用[J]。 世界地震工程,1991,7(2):4-21。
[18] 林皋。岩土地震工程及土动力学新进展[J]。世界地工程,1992,5,2:1-11。
[19] 陈国兴.土体-结构体系的地震性能研究[J]. 哈尔滨建筑工程学院学报, 1994,10,27 (5):11-18.
[20] 肖晓春,林皋,迟世春。土-桩-结构动力相互作用的分析模型与方法[J]。世界地震工程,2002,4:123-130。
[21] 胡聿贤。地震工程学[M]。北京:地震出版社,1988。
[22] J. Peizien. Seismic Analysis of Bridges on Long Piles[J]. J. Engng. Mech. Div., ASCE, 1964, 90 (EM3):223-254.
[23] 宰金珉,宰金璋。高层建筑基础分析与设计-土与结构物共同作用的理论与应用[M]。北京:中国建筑工业出版社,1993。
[24] 周铭。弹性桩与弹性梁的通解[J]。岩土工程学报,1982,2,4(1):1-15。
[25] G.Gazetas, R.Dobry. Horizontal Response of Piles in Layered Soils[J]. Journal of Geotechnical Engineering, ASCE. 1984, 1,110(1):20-40.
[26] K.Fan, G.Gazetas. A.Kaynia. Kinematic Seismic Response of Single Piles and Pile Groups[J]. Journal of Geotechnical Engineering, ASCE, 1991, 12, 117 (12): 1860 -1879.
[27] N.Mrakis, G.Gazetas. Dynamic Pile-Soil-Pile Interaction Part II: Analysis of Lateral Vibration[J]. Earthquake Engineering and Structural Dynamics,1992,21: 145-162.
[28] 王立忠,柯瀚,陈云敏,吴世明。地震荷载作用下水泥搅拌桩的动力响应[J]。振动工程学报,1998,10,11(4):416-423。
[29] 林天剑,熊厚金,王利群。桩基础设计指南[M]。北京:中国建筑工业出版社,1999。
[30] Y.X.Cai, P.L.Gould, C.S.Desai. Evaluation of Seismic Response of Pile-Supported Structure with 3-D Nonlinear Approach[A]. Proceedings: 3th International Conference on Recent Advances in Geotecnical Earthquake Engineering and Soil Dynamic[C], 1995,Vol.III,St.Louis,Missouri, Paper No.5.45.
[31] Y.X.Cai, P.L.Gould, C.S.Desai. Nonlinear Analysis of 3D Seismic Interaction of Soil-Pile-Structure Systems and Application[J]. Engineering Structures, 2000,22,191-199.
[32] 李辉,赖明,白绍良。土-结构动力相互作用研究综述(II)[J]。重庆建筑大学学报,1999,10。
[33] Guoxi Wu, W.D.Liam Finn. Dynamic Elastic Analysis of Pile Foundations Using Finite Element Method in the Frequency Domain[J], Can. Geotech. J.1997,34: 34-43.
[34] Guoxi Wu, W.D.Liam Finn. Dynamic Nonlinear Analysis of Pile Foundations Using Finite Element Method in the Time Domain [J], Can. Geotech. J. 1997,34:44-52.
[35] W.D.Liam Finn,T Thavaraj, W D Wilson, et.al. Seismic Response Analysis of Pile Foundations at Liquefiable Sites[A], 12WCEE,2000, Paper No.0422.
[36] 刘汉龙,余湘娟。土动力学与岩土地震工程研究进展[J]。河海大学学报,1996,27(1):6-15。
[37] 刘晶波,吕彦东。结构-地基动力相互作用问题分析的一种直接方法[J]。 土木工程学报,1998,6,31(3):55-64。
[38] Poulos, H.G. and Davis, E.H. Pile Foundation Analysis and Design[M]. John Wiley and Sons, New York, 1980.
[39] 卢世深,林亚超编译。桩基础的计算与分析[M]。北京:人民交通出版社,1987。
[40] Desai C.S. Wathugala G.W. Constitutive Model for Cyclic Behavior of Clays II: Applications[J]. Journal of Geotechnical Engineering ASCE. 1993,119(4): 730– 749.
[41] G.Gazetae. et al. Seismic Response of End-Bearing Single Piles[J]. Soil Dynamics and Earthquake Engineering. 1984,3(2):82-93.
[42] J. Peizien, et al. Seismic analysis of bridges on long piles[J]. Journal of Engine. Mech. Div., ASCE, 1964,90 (EM3):223-254.
[43] 解明雨,孙焕纯。桩基础的高层建筑弹塑性地震反应分析[J]。大连工学院学报, 1983,6,22(2):9-16。
[44] 王有为,王开顺。建筑物-桩-土相互作用地震反应分析的研究[J]。建筑结构学报, 1985,5,64-73。
[45] 严士超,杜一平。电视塔-桩-土相互作用的地震反应分析[J]。土木工程学报,1991, (3): 71-79。
[46] Anagnostopoulos S. A. Pile foundation modeling for inelastic earthquake analyses of large structures [J]. Engineering Structures, 1983,5(2):15-22.
[47] 王有为,王开顺。地震作用下群桩水平刚度的计算方法及其程序设计[J]。土木工程学报, 1984, (1):39-48。
[48] GB50191-93,构筑物抗震设计规范[S]。北京:中国建筑出版社, 1993。
[49] K.J.Ahn, L.Gould. Interactive Base Isolation System: I. Finite Element Formulation [J]. Journal of Engineering Mechanics, ASCE. 1992, 10, 118 (10): 2048-2058.
[50] 钱家欢,殷宗泽。土工原理与计算[M]。北京:水利水电出版社,1994。
[51] 熊建国,王丹民,熊朝辉。考虑土-结构非线性相互作用下的结构地震反应分析[J]。建筑科学,1996,4,6-1。