高级搜索
  • 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引（EI）收录期刊
  • Scopus数据库收录期刊

利用弯曲元测量上海原状软黏土各向异性剪切模量的试验研究

吴宏伟, 李青, 刘国彬

吴宏伟, 李青, 刘国彬. 利用弯曲元测量上海原状软黏土各向异性剪切模量的试验研究[J]. 岩土工程学报, 2013, 35(1): 150-156.
引用本文: 吴宏伟, 李青, 刘国彬. 利用弯曲元测量上海原状软黏土各向异性剪切模量的试验研究[J]. 岩土工程学报, 2013, 35(1): 150-156.
shu
C. W. W. Ng, LI Qing, LIU Guo-bin. Measurements of small-strain inherent stiffness anisotropy of intact Shanghai soft clay using bender elements[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(1): 150-156.
Citation: C. W. W. Ng, LI Qing, LIU Guo-bin. Measurements of small-strain inherent stiffness anisotropy of intact Shanghai soft clay using bender elements[J]. Chinese Journal of Geotechnical Engineering, 2013, 35(1): 150-156.
shu

利用弯曲元测量上海原状软黏土各向异性剪切模量的试验研究  English Version

  • 1. 香港科技大学土木及环境工程系，香港；2. 同济大学地下建筑及工程系，上海 200092

基金项目: 香港研究资助局（RGC）项目（GRF-617608，617410）
详细信息
    作者简介:

    吴宏伟（1962- ），男，剑桥大学土力学及岩土工程专业博士后，香港科技大学讲座教授与土工离心机实验室主任，教育部长江学者奖励计划讲座教授，国际岩土力学与土力工程学会理事，英国特许工程师，剑桥大学丘吉尔学院海外院士。主要从事土基与建筑物的相互作用（包括桩土相互作用、深基坑及隧道开挖对周围环境的影响）、土工离心模型试验、非饱和土及边坡稳定方面的研究工作。E-mail: cecwwng@ust.hk。

  • 中图分类号: TU411

Measurements of small-strain inherent stiffness anisotropy of intact Shanghai soft clay using bender elements

  • 1. Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China; 2. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China

摘要

    摘要
  • 摘要: 在许多发达国家例如英国，土体的小应变特性已被广泛应用于预测地下建筑物施工引起的地表变形。尽管上海的城市地下基础、基坑与隧道开挖日益增多，但是关于上海原状软黏土小应变剪切模量的研究几近空白。利用装有霍尔局部应变传感器与弯曲元测试系统的三轴仪对上海软黏土剪切刚度的固有各向异性进行了研究。在等向应力状态下对方形原状上海软黏土试样进行了两组试验。试验结果表明：较之传统的初达波法和峰-峰法，互相关法一定程度上提高了弯曲元试验中确定剪切波速的客观性。由于土体水平向层理结构与颗粒间胶结作用的影响，上海软黏土呈现出明显的各向异性，实测最大剪切刚度的固有各向异性比（G0(hh)/G0(hv)）约为1.21。利用孔隙比函数F(e)=e-1.3能够很好的描述不同平面内最大剪切模量与土体应力状态的相互关系。
    Abstract: Measurements of small-strain stiffness are widely used for predicting ground movements in many developed countries such as the UK. Although an increasing number of foundations, excavations and tunnels are constructed in Shanghai, the measurements of the small-strain shear modulus of Shanghai soft clay have rarely been reported. In this study, the degree of inherent stiffness anisotropy of intact Shanghai soft clay is investigated using a triaxial apparatus equipped with Hall-effect local strain transducers and a bender element testing system. Two series of tests are carried out on intact prismatic soil specimens under an isotropic stress state. The experimental results reveal that the cross-correlation method using two received signals gives rise to more objective and repeatable results than the conventional first-arrival-time and peak-to-peak methods. The intact Shanghai soft clay clearly exhibits inherent stiffness anisotropy, as demonstrated by its elastic shear modulus ratio (G0(hh)/G0(hv)) of about 1.21, due to the stronger layered structure in the horizontal plane and a bonding effect. A unique relationship is found and established between the normalized shear modulus and the stress state in each plane by incorporating a void ratio function in the form of F(e)=e-1.3.
    • HTML全文
    • 参考文献(23)
  • [1] LEE K M, ROWE R K. Deformations caused by surface loading and tunnelling: the role of elastic anisotropy[J]. Géotechnique, 1989,39(1):125-140
    [2] SIMPSON B, ATKINSON J H, JOVIČIĆ V. The influence of anisotropy on calculations of ground settlements above tunnels[J]. Geotechnical Aspects of Underground Construction in Soft Ground, 1996:591-594
    [3] NG C W W, LEUNG E H Y, LAU C K. Inherent anisotropic stiffness of weathered geomaterial and its influence on ground deformations around deep excavations[J]. Canadian Geotechnical Journal, 2004,41(1):12-24
    [4] JOVIČIĆ V, COOP M R. The measurement of stiffness anisotropy in clays with bender element tests in the triaxial apparatus[J]. Geotechnical Testing Journal, 1998,21(1):3-10
    [5] BELLOTTI R, JAMIOLKOWSKI M, LO PRESTI D C F,et al. Anisotropy of small strain stiffness in Ticino sand[J]. Geotechnique, 1996,46(1):115-131
    [6] FIORAVANTE V. Anisotropy of small strain stiffness of ticino and kenya sands from seismic wave propagation measured in triaxial testing[J]. Soils and Foundations, 2000,40(4):129-142
    [7] PENNINGTON D S, NASH D F T, LINGS M L. Anisotropy of G0 shear stiffness in Gault clay[J]. Géotechnique, 1997,47(3):391-398
    [8] NG C W W, LEUNG E H Y. Determination of shear-wave velocities and shear moduli of completely decomposed tuff[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2007,133(6):630-640
    [9] WANG Y H, MOK C B. Mechanisms of small-strain shear-modulus anisotropy in soils[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2008,134(10):1516-1530
    [10] JAMIOLKOWSKI M, LANCELLOTTA R, LO PRESTI D C F. Remarks on the stiffness at small strain of six Italian clays[C]// Proceedings of International Symposium on Pre-failure Deformation of Geomaterials, Sapporo, Japan, 1994, 2: 817-836.
    [11] TEACHAVORASINSKUN S, LUKKANAPRASIT P. Stress induced and inherent anisotropy on elastic stiffness of soft clays[J]. Soils and Foundations, 2008,48(1):127-132
    [12] HARDIN B O, BLANDFORD G E. Elasticity of particulate materials[J]. Journal of Soil Mechanics and Foundations Division, ASCE,1989, 115(2):1449-1467
    [13] CLAYTON C R I, KHATRUSH S A, BICA A V D, SIDDIQUE A. Use of hall effect semiconductors in geotechnical instrumentation[J]. Geotechnical Testing Journal, 1989,12(1):69-76
    [14] ANDRESEN A, KOLSTAD P. The NGI 54 mm sampler for undisturbed sampling of clays and representative sampling of coarser materials[C]// Proceedings of the International Symposium on State of the Art on Current Practice of Soil Sampling, Singapore, 1979: 13-21.
    [15] LUNNE T, BERRE T, STRANDVIK S. Sample disturbance effects in soft low plastic Norwegian clay[C]// Proceedings of Symposium on Recent Developments in Soil and Pavement Mechanics, Rio de Janeiro, Brazil, 1996: 81-102.
    [16] CLAYTON C R I, THERON M, BEST A I. The measurement of vertical shear-wave velocity using side-mounted bender elements in the triaxial apparatus[J]. Géotechnique, 2004,54(7):495-498
    [17] VIGGIANI G, ATKINSON J H. Interpretation of bender element tests[J]. Géotechnique, 1995,45(1):149-154
    [18] ALVARADO G, COOP M R. On the performance of bender elements in triaxial tests[J]. Géotechnique, 2012,62(1):1-17
    [19] WANG Y H, LO K F, YAN W M, DONG X B. Measurement biases in the bender element test[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2007,133(5):564-574
    [20] 龚士良,茅鸿妹. 上海软黏土微观特性及在土体变形中的作用[J]. 上海地质, 1999,52:29-35. (GONG Shi-liang, MAO Hong-mei. The microcosmic characteristics in Shanghai soft clay and its effect in soft body movement[J]. Shanghai Geology, 1999, 52, 29-35. (in Chinese))
    [21] CLAYTON C R I, HIGHT D W, HOPPER R J. Progressive destructuring of Bothkennar clay: implications for sampling and reconsolidation procedures[J]. Géotechnique, 1992,42(2):219-239
    [22] CLAYTON C R I, HEYMANN G. Stiffness of geomaterials at very small strains[J]. Géotechnique, 2001,51(3):245-255
    [23] LO PRESTI D C F. Proprietà dinamiche dei terreni[C]// XIV Conferenza Geotecnica di Torino, Dept. of Structural Engineering, Politecnico di Torino,1989
    LO PRESTI D C F. Dynamic properties of soils[C]// Proceedings of XIV Geotechnical Conference, Turin, Italy, 1989. (in Italian))
    • 相关文章
    • 施引文献
    • 资源附件(0)
计量
  • 文章访问数:  1104
  • HTML全文浏览量:  9
  • PDF下载量:  677
  • 被引次数: 0
出版历程
  • 收稿日期:  2012-03-21
  • 发布日期:  2013-01-31

目录

摘要
HTML全文
    参考文献(23)
    相关文章
    施引文献
    资源附件(0)

    /

    返回文章
    返回
    版权所有 © 2010水利部交通部国家能源局南京水利科学研究院 苏ICP备05007122号-11公安联网备案号：32010602011255
    编辑部地址：南京市虎踞关34号《岩土工程学报》编辑部邮编：210024电话：025-85829534，85829556E-mail: ge@nhri.cn