摘要
为进一步探讨岩溶洞穴盖层稳定性分析方法,运用ANSYS软件对不同尺寸共36个洞穴模型进行了模拟分析,得到了关于地表拉压应力区范围的线性拟合公式;根据地表压应力区范围和洞穴跨径大小将其分为Ⅰ型和Ⅱ型洞穴,并对塌落体周界水平应力分布进行了修正,采用极限平衡理论得到了岩溶洞穴盖层塌落体稳定系数计算式。实例分析表明,跨径为6 m的Ⅰ型洞穴盖层塌落体稳定系数随半径呈先减小后增大的趋势,稳定性最差的塌落体半径约1.4 m,即该洞穴容易局部失稳发生坛形塌陷,计算结果与现实情况较为吻合,表明本文中提出的岩溶洞穴土质盖层稳定性计算方法具有一定的理论参考价值。
For further study on stability calculation methods of cover layer for Karst cave,a total of 36 cave models with different size were simulated by ANSYS software. According to the simulation results,the linear fitting formula about tension and compression area on the earth was obtained. At the same time,according to the relation between the compressive stress zone and the span size of cave,it was divided into cave type I and type II. What else,the article had also modified the distribution of horizontal stress for the fall mass and using the limit equilibrium theory to get the stability calculation formula of cover layer for Karst cave. Through the example analysis we can acquire that when the span size of cave type I is 6 meters the stability coefficient of fall mass is decreasing firstly and then increasing,and the radius of fall mass with the worst stability is about 1. 4 meters so that altar shape collapse is likely to happen. The calculation results are in good agreement with the real situation and it shows that the stability calculation methods of cover layer for Karst cave proposed in this article has certain value for theoretical reference.
出处
《地下空间与工程学报》
CSCD
北大核心
2016年第2期546-552,共7页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(51378521)
重庆市国土科技项目(CQGT-KJ-2014026
CQGT-KJ-120301)
重庆市"两江学者"计划专项经费资助
2013年重庆高校创新团队建设计划资助项目(KJTD201305)
关键词
塌陷
稳定性
极限平衡
塌落体
岩溶地区
collapse
stability
limit equilibrium
fall mass
karst area
