长江科学院院报 ›› 2017, Vol. 34 ›› Issue (2): 56-62.DOI: 10.11988/ckyyb.20161014

• 加筋机理及加筋土结构 • 上一篇    下一篇

岩溶塌陷影响下加筋路基承载机理研究

万梁龙1,陈福全2,邹维列1   

  1. 1.武汉大学 土木建筑工程学院,武汉 430072;
    2. 福州大学 土木工程学院,福州 350116
  • 收稿日期:2016-07-01 修回日期:2016-08-15 出版日期:2017-02-01 发布日期:2017-02-08
  • 通讯作者: 陈福全(1971-),男,福建漳平人,教授,博士,从事岩土工程教学与研究工作,(电话)13600801026(电子信箱)phdchen@163.com。
  • 作者简介:万梁龙(1991-),男,四川达州人,博士研究生,研究方向为土工合成材料及土体加固,(电话)15280106948(电子信箱)wanlianglong@126.com。
  • 基金资助:
    国家自然科学基金项目(41572253);高等学校博士学科点专项科研基金博导类资助课题项目(20133514110004)

Mechanisms of Load Transfer in Geosynthetic-reinforced Embankments Subjected to Localised Karst Collapse

WAN Liang-long1, CHEN Fu-quan2, ZOU Wei-lie1   

  1. 1.School of Civil Engineering, Wuhan University, Wuhan 430072, China;
    2.College of Civil Engineering, Fuzhou University, Fuzhou 350116, China
  • Received:2016-07-01 Revised:2016-08-15 Online:2017-02-01 Published:2017-02-08

摘要: 在可能发生岩溶塌陷的地区建造路堤,可采用在路堤底部铺设土工合成材料加筋垫层的方法加固路基,防止岩溶突然坍塌造成路堤塌陷。采用PLAXIS3D软件,运用更新网格的大变形有限元分析方法,研究加筋路基在岩溶塌陷影响下路堤和筋材位移、应力场分布规律及加筋路基的承载机理,分析了岩溶塌陷尺寸、路堤填土高度、筋材抗拉刚度和路堤填土性质对地表最大沉降和最大拉力的影响。结果表明,地表最大沉降与路堤中是否形成封闭的应力穹顶密切相关,封闭的应力穹顶高度主要受塌陷尺寸和路堤填土黏聚力影响;筋材抗拉刚度、路堤高度和路堤填土内摩擦角对封闭的应力穹顶高度影响较小;筋材横纵向最大拉力按筋材横纵向抗拉刚度比例分配,单向与双向加筋差别不大。

关键词: 岩溶塌陷, 加筋路基, 承载机理, 数值分析, 土拱效应

Abstract: Geosynthetics could be used for reinforcing embankment subjected to the influence of potential localised karst collapse. In this paper, the displacements and stresses in both embankment and geosynthetics, and the bearing mechanism of geosynthetic-reinforced embankment are analyzed in detail based on the numerical simulation results from PLAXIS3D software by using large deformation analysis method with updated mesh function. Moreover, the influences of design parameters (including size of karst collapse, embankment height, geosynthetic’s tensile stiffness and properties of embankment soil) on the maximum settlements of embankment and the maximum tensions of geosynthetics are investigated. Results indicate that the maximum settlement of embankment is depended on whether a closed stress dome in embankment is formed, and the height of the stress dome is mainly related to the size of collapse and the cohesion of embankment soil. Geosynthetic’s tensile stiffness, embankment height, and internal friction angle of embankment fill have slight influence on the height of stress dome. The maximum longitudinal and transverse tensions of geosynthetics are related to the longitudinal and transverse stiffness of geosynthetics, and the differences of both maximum pavement settlement and strain in geosynthetics caused from uniaxial and biaxial geogrids are small.

Key words: localised karst collapse, geosynthetic-reinforced embankment, bearing mechanism, numerical analysis, soil arching effect

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