土工基础

›› 2013, Vol. 27 ›› Issue (6): 51-54.

• 工程实录 • 上一篇    下一篇

椭球状溶洞上方路基稳定性数值分析

林智勇1,2，戴自航1   

  1. (1.福州大学 岩土工程研究所,福州〓350108;2.福建工程学院 土木工程学院,福州〓350108)
  • 收稿日期:2013-03-07 出版日期:2013-12-20 发布日期:2013-12-21
  • 作者简介:林智勇(1982-)，男，在读博士研究生，讲师，研究方向为岩土体稳定性分析、桩基工程等的教学与数值。 通讯作者：戴自航，教授，博导。
  • 基金资助:

    福建省自然科学基金资助项目（2011J01308）；福建省交通规划设计院委托项目

Numerical Analysis of Highway Subgrade above an Elliptical Karstic Rock Cavern

LIN Zhiyong1,2， DAI Zihang1   

  1. (1.Institute of Geotechnical Engineering, Fuzhou University, Fuzhou 350108;2.College of Civil Engineering, Fujian University of Technology, Fuzhou 350108)
  • Received:2013-03-07 Online:2013-12-20 Published:2013-12-21

摘要： 以某岩溶区高速公路为例，利用三维数值模拟，采用稳定安全系数、潜在破坏面（剪应变率及塑性区的贯通）作为失稳判据，分析了溶洞顶板厚度、顶板形式及路基坡脚与溶洞水平距离等因子对椭球状溶洞上方路基稳定性及路基顶面与基底面沉降的影响。结果表明，不同条件下，路基沉降均呈漏斗状，且随着顶板厚度的增大，路基顶面及基底面沉降逐渐变小，沉降漏斗变小，稳定安全系数变大，达到一定值后趋于稳定；椭球状溶洞路基失稳破坏形式分别以顶板岩层的拉裂破坏及路基填土的剪切破坏为主，而水平顶板则以冲剪破坏形式为主；对于椭球状溶洞，顶板安全厚度远小于同等条件下水平顶板的安全厚度。

关键词: 数值模拟, 椭球状溶洞, 路基, 稳定性, 潜在破坏面

Abstract: This paper presents the numerical analysis results of the stability of highway subgrade above an elliptical karstic rock cavern. The factor of safety, development of the potential failure plane, which defined as the connection of the plastic zones and the shear strain rates, are used as the failure criteria. The thickness of the overburden material, shape, horizontal distance of the embankment toe to the cavern on the stability of the highway subgrade above the elliptical karst rock cavern are investigated. The results indicate that the settlement shape of the subgrade is a cone type and the magnitude of the settlement is reduced with the increase of the overburden material. The factor of safety will also increase and tends to stable. The failure patterns of the subgrade above the cavern are: tensile failure of the overburden rock and shear failure of the embankment above. For ellipsoid karstic rock cavern, the roof thickness was less than that for horizontal cavern roof.

Key words: Numerical Analysis, Elliptical Karstic Rock Cavern, Embankment Subgrade, stability, Potential Failure Surfaces