中文摘要：

本文在综合分析岩溶区溶洞顶板稳定性常用计算方法的基础上，结合岩溶区路基溶洞顶板工程特点及溶洞顶板受力特性，建立出符合其工程特点的岩溶区路基溶洞顶板稳定性分析的力学模型，再运用弹性理论基本原理，导出岩溶区路基溶洞顶板岩层应力计算公式，并引入修正的Mohr—Coulomb强度理论，建立出岩溶区路基溶洞顶板安全厚度确定新方法。将该方法应用于某实际工程溶洞顶板的稳定性分析，效果良好，最后对影响溶洞顶板稳定性的各种主要因素进行了深入分析，获得了一些定性的结论。

英文摘要：

According to the engineering features of subgrade karst roof in karst regionand mechanics performance of subgrade karst roof in karst region, a mechanical model of stability analysis on cave roof is established based on the analysis of stability calculating methods used commonly. And then, the stress calculation formulation of subgrade cave roof in karst region is deduced through applying the basic principle of elasticity theory. Moreover, a new method determining on cave roof safe thickness in karst region is established by introducing the modified Mohr-Coulomb strength theory. At the same time, a practical engineering project is applied to verify this method, which has been proved successfully. At last, the major effect factors of stability on cave roof under pile in karst region are deeply discussed and some results in quality are acquired.