岩溶地质特征下的溶洞地基处治研究

为研究贵州某机场在岩溶地质特征下的溶洞地基处治,通过对岩溶环境开展调研,依据工程勘察报告及机场岩溶发育特征,结合工程实际设计施工及检测成果,研究溶洞地基处理适应性处治技术。主要用强夯法处理岩溶洼地、漏斗、塌陷、落水洞,以及充填类型的洞体等溶洞地基;用清爆强夯法处理隐伏溶洞;用地面搅拌高压灌注C15号混凝土处理未充填或半充填类型的洞体。实验结果表明:强夯处理的溶洞的固体体积率大于78%的设计要求,波速测试无明显空洞;清爆强夯处治溶洞固体体积率均大于83%;C15低标号混凝土处理的溶洞混凝土取芯率不小于80%,并无明显掉钻,重型动力触探N63.5均大于5击,波速测试无明显空洞。

Study on Treatment of Karst Cave Foundation under Karst Geological Characteristics

In order to study the karst cave foundation treatment of an airport in Guizhou under the karst geological characteristics,through the investigation of the karst environment,according to the engineering survey report and the airport karst development characteristics,and combined with the actual design,construction and detection results of the project,the adaptive treatment technologies of the karst cave foundation are analyzed,mainly using the dynamic consolidation method to treat the karst depression,funnel,collapse,aven and filled caves,using the clear blasting dynamic consolidation method to treat the latent karst caves and using the ground mixing and high-pressure pouring of C15 concrete to treat the unfilled and semi-filled caves.The experimental results show that the solid volume ratio of the karst cave treated by the dynamic consolidation is greater than 78%of the design requirements.There are no obvious voids in the wave velocity testing.The solid volume ratio of the karst cave treated by the clear blasting dynamic consolidation is more than 83%.The coring rate of karst cave concrete treated by the C15 low-grade concrete is not less than 80%and without obvious loss of drill.The heavy-duty dynamic sounding N63.5 is all greater than 5 hits,and there are no obvious voids in the wave velocity testing.