数值分析

地应力对路基下伏溶洞稳定性的影响

展开
  • 1. 长安大学 特殊地区公路工程教育部重点实验室,陕西 西安 710064;2. 江西省交通科学研究院,江西 南昌 330052; 3. 江西省高速公路投资集团有限责任公司,江西 南昌 341000
张震,男,1990年生,博士研究生,从事道路与铁道工程方面研究工作。

收稿日期: 2016-04-12

  网络出版日期: 2018-06-09

基金资助

江西省交通运输厅科技项目(No.2015C0022)

Effect of in-situ stress on stability of underlying karst cave

Expand
  • 1. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang’an University, Xi’an, Shannxi 710064, China; 2. Transportation Science Institute of Jiangxi Province, Nanchang, Jiangxi 330052, China; 3. Jiangxi Provincial Expressway Investment Group Co., Ltd., Nanchang, Jiangxi 341000, China

Received date: 2016-04-12

  Online published: 2018-06-09

Supported by

This work was supported by Technology Program of Jiangxi Transportation Hall (2015C0022).

摘要

为研究地应力对溶洞稳定性的影响,依据中国大陆地壳应力环境基础数据库及地应力分布规律计算公式建立了地应力模型,并辅以少量的测孔予以验证。基于地应力、Hoek-Brown屈服准则等模型,利用有限差分软件,结合剪应力分析和塑性区分析,针对不同地应力环境下溶洞的剪应力变化情况和破坏特点进行分析和总结发现,溶洞的稳定性与其所处的地应力环境存在很大关系。将地应力分解为静水应力和剪切应力,回归分析绘制趋势图发现静水应力和剪切应力之间的比值与溶洞可以承载的极限路基高度近似为负相关的线性关系。对沿线岩溶塌陷位置以及实测的路基填筑高度进行统计,并与预测成果对比发现地应力对溶洞稳定性的影响不可忽略。

关键词: 溶洞; 稳定性; 地应力; 塑性

本文引用格式

张 震,陈忠达,朱耀庭,胡文华,吴福泉,刘超群, . 地应力对路基下伏溶洞稳定性的影响[J]. 岩土力学, 2016 , 37(S2) : 715 -723 . DOI: 10.16285/j.rsm.2016.S2.091

Abstract

In order to analyze the influence of geostress on the stability of karst cave, a geostress model was developed based on the geostress database in China and the geostress formula in the research region. In-situ measurement was executed to bridge the gap between the geostress model and the engineering application. For the convince of evaluating the magnitude of shear stress and plastic zone, the karst cave was modeled through the finite difference software with applications of the geostress model and Hoek-Brown yield criterion. Special attention is paid to the stability evaluation of the karst cave under various geostress conditions during modelling. Several beneficial consequences obtained from the evaluation suggest that the role of the geostress condition is quite important in influencing the stability of karst cave. The geostress is decomposed into the mean stress and the shear stress for the sake of exploring its explicit influcement. An empirical equation was summarized via regression analysis to explicitly depict the approximately linear relationship between the ratio between the mean stress and the shear stress and the capability of karst cave. An in-situ investigation considering the collapse site and the ultimate subgrade height was conducted to compare with the numerical results. The results suggest that a reasonable consideration of geostress is necessary for evaluating the stability of karst cave.
文章导航

/