用户名: 密码: 验证码:
虚土桩法可行性初步研究与分析
详细信息    本馆镜像全文|  推荐本文 |  |   获取CNKI官网全文
摘要
虚土桩法是为了解决桩与桩侧土、桩端土相互作用而提出的一种新方法,该方法将桩端投影面以下直到基岩的土层看成为“土桩”,建立土体动力平衡方程、桩体和虚土桩体动力平衡方程,并结合具体边界条件来研究桩土耦合振动特性。虚土桩法可以考虑桩与桩侧土、桩端土的耦合作用,桩端以下土体的非均质性和成层性,基岩埋置深度的影响以及沉降随时间发展的过程等多方面因素,具有广阔的应用前景。
     本文基于虚土桩思想,进行了以下三方面的研究:
     1、结合土体平衡方程和虚土桩体平衡方程,对静力条件时刚性圆盘下弹性地基表面和内部的应力场和位移场进行研究,得到了虚土桩中心线和不同深度土层竖向应力和位移的分布以及虚土桩顶的刚度。同时分析影响土体竖向应力和位移分布的各种因素,并与其他学者的研究成果进行对比,分析虚土桩法在刚性圆盘下地基静力分析时的适用性。
     2、结合土体动力平衡方程和虚土桩体动力平衡方程,对简谐荷载时刚性圆盘下均质滞回材料阻尼土体的振动特性进行研究,得到了土层阻抗因子、桩顶位移幅频、桩顶复刚度、速度导纳等振动特性,同时分析影响上述振动特性的各种因素,并与其他学者的研究成果进行对比。
     3、结合单桩沉降计算的荷载传递法,根据桩及虚土桩体平衡方程、接触面处力和位移的相容条件,得到弹性状态下单桩沉降解析解。结合单桩沉降的弹性理论法,采用Mindlin位移解,考虑桩和虚土桩侧摩阻力的相互作用,得到单桩沉降的解析解。根据土体平衡方程、桩体平衡方程和虚土桩体平衡方程,结合边界条件和相容条件,得到桩顶沉降的解析解。对上述三种方法得到的桩顶荷载-沉降关系进行对比,并分析桩长、泊松比、桩土弹性模量、虚土桩长度等因素的影响。同时与现有的荷载传递法和弹性理论法进行对比,分析虚土桩法的可行性。
     本文对虚土桩法在地基静动力特性和单桩沉降计算中应用的可行性和适用条件进行的初步分析,推动了虚土桩法在桩的动静特性方面的应用研究。
Method of virtual pile of soil is a new method to solve the interaction between pile and the soil under the pile. In this method, the soil between pile tip and bedrock is taken as a virtual pile to study the dynamic soil-pile interaction problem. Then the interaction between soil and pile, non-homogeneity or stratification of the soil, depth of the bedrock and settlement of pile over time can be taken into consideration in analysis of pile dynamic or static characteristics. Therefore, method of virtual pile of soil has broad prospects for application.
     This thesis which is based on the method of virtual pile of soil has done the main original work as follows:
     1. The static equilibrium equations of soil and virtual pile are solved according to the boundary condition and the stress and displacement fields of elastic soil under a rigid circular plate are investigated. The vertical stress and displacement along the center line of the virtual pile and at various depths is investigated and the stiffness at the top of virtual pile is studied. Some main influencing factors, such as the length of virtual pile, Poisson's ratio, modulus of soil are analyzed to illustrate the distribution of vertical stress and displacement. Meanwhile, the results are compared with other existing researches to illustrate the applicability of the virtual pile of soil method.
     2. According to the dynamic equilibrium equations of soil and virtual pile, dynamic characteristics of hysteretic damping soil under a rigid circular plate at the harmonic load are investigated. The influence on the resistance factor and vibration modes of soil, curves of settlement-frequency, complex stiffness-frequency and mobility wave-frequency of virtual pile caused by length of virtual pile, Poisson's ratio and hysteretic damping ratio is discussed. And the relationship of complex stiffness and frequency is compared with other existing researches.
     3. Firstly, according to the static equilibrium equations of pile and virtual pile and the consistency conditions at the interface, the analytic solution of single pile settlement based on the load transfer method is yielded. Secondly, using the elastic theory method based on Mindlin's displacement solution, the analytic solution of single pile settlement is obtained when the interaction of the shear stress along the pile and the virtual pile is considered. Thirdly, combining the static equilibrium of soil, pile and virtual pile with the boundary and consistency conditions, the analytic solution of the settlement at the pile top is obtained. Finally, influencing factors, such as length of pile and virtual pile, modulus of pile and soil are analyzed and the load-settlement curves of the three methods above are compared. Meanwhile, the results are compared with other existing researches to illustrate the feasibility of virtual pile of soil method.
     The preliminary feasibility studies and analysis in this thesis will promote the development of researches in the static and dynamic characteristics of piles using virtual pile of soil method.
引文
[1]A.C.Eringen,E.S.Suhubi,Elastodynamics(弹性动力学),石油工业出版社,1984
    [2]Awojobi A.O.,Vertical vibration of a rigid circular foundation on Gibson soil,Geotechnique,1972,22(2),p333-p343
    [3]Awojobi A.O.,Estimation of the dynamic surface modulus of a generalized Gibson soil from the rocking frequency of rectangular foundations,Geotechnique,1973a,23(1),p23-p31
    [4]Awojobi A.O.,Plane strain and axially symmetric problems of a linearly nonhomogeneous elastic half-space,Mech.Appl.Math.,1973b,ⅩⅨⅥ(3),p285-p302
    [5]Baranov V.A.,On the calculation of excited vibrations of an embedded foundation,Voprosy Dynamiki i Prochnocti,Polytechnic Institute of Riga,1967,p195-p209
    [6]Biot M.A.,Theory of propagation of elastic waves in a fluid-saturated porous solid Ⅰ.low-frequencyrange,J.Acoust.Society America,1956,28(2),p168-p178
    [7]Biot M.A.,Theory of propagation of elastic waves in a fluid-saturated porous solid Ⅱ.higher-frequency range,J.Acoust.Society America,1956,28(2),p179-p191
    [8]Biot M.A.,Theory of deformation of a porous viscoelastic anisotropic solid,J.Appl.Phys,1956,27(5),p459-p467
    [9]Biot M.A.,Mechanics of deformation and acoustic propagation in porous media,J.Appl.Phys.,1962,33(4),p1482-p1498
    [10]Butterfield R.,Banerjee P.K.,The elastic analysis of compressible piles and pile groups,Geotechnique,1971,21(1),p43-p60
    [11]Cooke J.C.,A solution of Tranter's dual integral equations problem,Quart.J.Mech.and Applied Math.,1956,9,p103-p110
    [12]Cooke R.W.,The settlement of friction piles foundations,Proceedings,Conference on tall buildings,KualaLumpur,Malaysia,1974
    [13]D'Appolonia E.,Romualdi J.P.,Load transfer in end-bearing steel H-piles,J.S.M.F.D.,1963,89(2),p1-p25
    [14]Eva Part-Enander等,Matlab 5手册,机械工业出版社,2000
    [15]Gardner W S,Consideration in the design of drilled piers,Design,Construction and Performance of Deep Foundation,1975
    [16]Gibson R.E.,et al,Some results concerning displacements in a non-homogeneous elastic layer,Journal of applied mathematics and physics(ZAMP),1971,22,p855-p864
    [17]H.G.Poulos,E.H.Davis,Pile Foundation Analysis and Design,John Wiley & Sons,1980,p74-p83
    [18] Kezdi A., The bearing capacity of piles and pile group, Proceedings of 4~(th) International Conference on Soil Mechanics and Foundation Engineering, London, 1957, p46-p51
    [19] Kraft L M, Ray R P, Kagawa T, Theoretical development of t-z curves, Journal of Geotechnical Engineering, 1981, 107(11), p1543-p1561
    [20] Krenk S., Schmidt H., Vibration of an elastic circular plate on an elastic half space-a direct approach, 1981, 48(1), p161-p168
    [21] Lamb H., On the propation of tremors over the surface of an elastic solid, Philosophical transaction of the royal society of London, 1904, 203, p 1 -p42
    [22] Luco J. E., Westmann R. A., Dynamic response of a rigid footing bounded to an elastic half-space, J. Appl. Mech., 1972, 39, p527-p534
    [23] Luco J. E., Impedance functions for a rigid foundation on a layered medium, Nuclear Engineering and Design, 1974, 31, p204-p217
    [24] Luco J. E., Vibrations of a rigid disc on a layered viscoelastic medium, Nuclear Engineering and Design, 1976, p325-p340
    [25] Luco J. E., On the relation between radiation and scattering problems for foundations embedded in an elastic half-space, Soil Dynamics Earthquake Engineering, 1984, 5, p97-101
    [26] M. Novak, Vertical vibration of floating piles, Journal of the Engineering Mechanics Division, ASCE, 1977, 103 (EMD, p153-p168
    [27] Mindlin R. D., Force at a point in the interior of a semi-infinite solid, Physics, 1936, 5
    [28] Muki R., Sternberg E., On the diffusion of an axial load from an infinite cylindrical bar embedded in an elastic medium, Int. J. Solids and Struct., 1969, 5, p587-p606
    [29] Muki R., Sternberg E., Elastostatic load-transfer to a half space from a partially embedded axially loaded rod, Int. J. Solids and Struct., 1970, 6, p69-p90
    [30] Nogami T., Novak M., Soil-pile interaction in vertical vibration, Earthquake Engineering and Structure Dynamics, 1976, 4(3), p277-p293
    [31] Oien M. A., Steady motion of a rigid strip bonded to an elastic half space, J Appl Mech, 1971, 38(2), p328-p334
    [32] Quinlan P. M., The elastic theory of soil dynamics, Symp. On Dyn. Test of Soils, ASTM STP No., 1953, 156, p3-p34
    [33] Reissner E. Stationare, axislsymmetrische durch eine Schuttelnde Masse erregte Schwingungeneines homogenen elastischen Halbraumes, Ingenieur Archiv, 1936, 7(6), p381-p396
    [34] Sung T. Y., Vibration in semi-infinite solids due to periodic surface loading. ASTM Spec Techn Publ, 1953, 156, p35-p63
    [35]Thomson W.T.,Transmission of elastic waves through a stratified medium,J.Appl.Phys.,1950,21,p89-p93
    [36]Vijayvergiya V.N.,Load-movement characteristics of pile,Coastal and Ourbam N.C.,Thesis Presented to Duke University,1975
    [37]Zeng X.,Rajapakse.R.K.N.D,Dynamics axial load transfer from elastic bar to poroelastic medium,Journal ofEngineeringMechanics,ASCE,1999,125(9),p1048-p1055
    [38]曹汉志,桩的轴向荷载及荷载.沉降曲线的数值计算方法,岩土工程学报,1986,18(6)
    [39]陈龙珠等,桩轴向荷载-沉降曲线的一种解析算法,岩土工程学报,1994,16(6),p31-p38
    [40]陈龙珠,陈胜立,饱和地基上刚性基础的竖向振动分析,岩土工程学报,1999,21(4),p392-p397
    [41]刁元胜,积分变换,华南理工大学出版社,2003
    [42]杜秦文,土体剪切模量随深度连续变化非均质地基解析研究,2005,浙江大学博士学位论文
    [43]杜秦文等,双层广义Gibson地基轴对称问题求解,岩土力学,2007.5,28(5),p933-p938
    [44]费勤发等,桩土共同作用的位移影响系数的计算,力学季刊,1983,(04)
    [45]官全美,基于Mindlin位移解的群桩沉降计算,地下空间,2001,21(3),p167-p177
    [46]郭大智,钟阳,刚性承载板下弹性多层连续体应力和位移分析,哈尔滨建筑大学学报,1995,28(2),p17-p22
    [47]何钟怡等,关于复阻尼理论的几点注记,地震工程与工程振动,2002,22(1),p1-p6
    [48]胡昌斌,考虑土竖向波动效应时成层土中桩土纵向耦合振动理论,2003,浙江大学博士学位论文
    [49]胡海岩,结构阻尼模型及系统时域动响应,应用力学学报,1993,10(1),p34-p43
    [50]金波,层状地基及其动力基础基础,1994,浙江大学博士学位论文
    [51]金波,唐锦春,粘弹性半空间上刚体的垂直振动,固体力学学报,1996,17(2),p179-p184
    [52]金波等,层状地基轴对称问题的Mindlin解,计算结构力学及其应用,1996,13(2),p187-p200
    [53]金波,层状半空间地基上刚性圆板的垂直振动,同济大学学报,1997,25(3),p369-p373
    [54]李强,考虑三维波动的饱和土中桩纵向耦合振动理论,2004,浙江大学博士学位论文
    [55]雷林源,桩基动力学,冶金工业出版社,2000
    [56]栾茂田,孔德森,单桩竖向动力阻抗计算方法及其影响因素分析,振动工程学报,2004,17(4),p500-p505
    [57]吕凡任等,一种基于Mindlin解的直桩沉降弹塑性分析方法,岩石力学与工程学报,2004,23(17),p2988-p2991
    [58]孟凡顺等,层状弹性半空间轴对称静力问题的奇异解,西北工业大学学报,1997,15 (2),p300一p304
    [59]潘时声,桩基础分层位移迭代法计算理论及其应用,1993,同济大学博士学位论文
    [60]潘时声,侯学渊,桩的刚度计算,岩土工程学报,1996,18(1),p1-p6
    [61]蒲俊等,Matlab 6.0数学手册,浦东电子出版社,2002
    [62]阙仁波,考虑土体三维波动效应时桩的纵向振动特性与应用研究,2004,浙江大学硕士学位论文
    [63]宋炎,张春,竖向荷载作用下桩基荷载传递计算方法,中国港湾建设,2007,152(6),p7-p10
    [64]王非等,单桩荷载传递法修正计算分析,公路交通科技,2007,24(10),p53-p57
    [65]王纪林等,特殊函数与数学物理方程,上海交通大学出版社,2000
    [66]王凯,N层弹性连续体在圆形均布垂直荷载作用下的力学计算,土木工程学报,1982,2,p65-p76
    [67]王伟,杨敏,竖向荷载下桩基础弹性分析的改进计算方法,岩土力学,2006,27(8),p1403-p1406
    [68]王旭东等,单桩荷载.沉降非线性分析,南京建筑工程学院学报,1994,No.1
    [69]吴世明等,土动力学,中国建筑工业出版社,2000
    [70]奚定平,贝塞尔函数,高等教育出版社,1998
    [71]谢康和,周健,岩土工程有限元分析理论与应用,科学出版社,2002
    [72]辛公锋,大直径超长桩侧阻软化试验与理论研究,2006,浙江大学博士学位论文
    [73]徐芝纶,弹性力学(第4版),高等教育出版社,2006
    [74]严人觉等,动力基础半空间理论概论,建筑工业出版社,1981,p356-p435
    [75]杨敏,分层土中的单桩分析法,同济大学学报,1992,20(4)
    [76]张永谋,单桩荷载传递性状研究,兰州铁道学院学报,2003,22(6),p92-p95
    [77]张忠苗,桩基工程,中国建筑出版社,2007
    [78]钟阳等,轴对称弹性半空间问题一般解的新方法,哈尔滨建筑大学学报,1995,28(2),p23-p27
    [79]周罡,林萌,用Mindlin应力解求单桩沉降的方法,地下空间,2001,2l(3),p173-p177
    [80]朱金颖等,层状地基中桩静载荷试验数据的拟合分析,岩土工程学报,1998,20(3),p34-p39
    [81]朱向荣等,岩层上非均质弹性地基轴对称问题求解,岩土工程学报,2005
    [82]朱照宏等,路面力学计算,人民交通出版社,1985

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700