复合地基区岩溶土洞的稳定性分析与加固技术

土洞塌陷和变形是威胁覆盖型岩溶区建筑物安全和正常使用的典型地质灾害,高速铁路因沉降标准高,对覆盖土层多采用了CFG桩、旋喷桩、搅拌桩等复合地基加固,对土洞的形成及发展起到了相当大的抑制作用。文中研究分析了复合地基加固条件下的土洞稳定性,以及土洞塌陷至路基基底时对垫层网结构的变形与拉力变化情况。提出了根据岩溶地基土洞塌陷的可能性进行分区,结合理论计算成果,合理确定岩溶地基加固措施的有关建议。

Analysis of Stability of Earth Cavity and Karst and Its Reinforcement Technology in Composite Foundation

In covered karst area,the collapse and deformation of earth cavity as the typical geohazards have more obvious influences to the safety and normal use of the structures.Because of high settlement criterion of high speed railway,composite foundations such as CFG piles,rotary jet grouting piles,mixing piles and so on are widely adopted in reinforcing Soil covering.And the piles can prevent greatly the form and development of earth cavity.This paper studys the stability of soil caves in composite foundation,and tensile stress and defomation of bedding network in subgrade.According to the development of karst and collapse probability of earth cavities,the zone of karst ground can be made.The reasonable reinforcement technology of karst ground are proposed in combination with calculated results.