岩溶发育地区某临海深基坑地下水控制及支护方法

Groundwater Control and Support Method of a Deep Foundation Pit Adjacent to Sea in Karst Development Area

该文介绍了在某临海、岩溶发育地区深基坑工程中地下水控制及支护的方法,该项目采用普通旋挖工艺施工的咬合桩,桩体内预埋钢套管,后续采用潜孔锤钻机钻至桩底以下7m深度,通过栓塞进行高压注浆来填充岩溶孔洞,从而较为经济地形成了上部咬合桩连续桩体和下部高压注浆止水帷幕,有效地减小了绕流量和渗漏量;结合坑内管井井点和有序明排、坑外管井适当降低水位确保锚索施工等技术,安全经济地进行了工程的开挖和地下结构的施工。

This paper introduces the method of groundwater control and support in a deep foundation pit project in a coastal and karst development area. The project adopts the bite pile constructed by the ordinary rotary excavation process, and the steel casing is embedded in the pile body. Subsequently, the DTH hammer drill is used to drill to a depth of 7 m below the pile bottom, and the karst hole is filled by high-pressure grouting through the plug, so as to economically form the continuous pile body interlocking pile in the upper and the water stop curtain of high-pressure grouting in the lower. The bypass flow and leakage are effectively reduced;Combination with the technologies of well points of pipe wells in the pit and orderly open drainage, and the pipe wells outside the pit to proper reduce the water level to ensure the construction of anchor cables, the excavation of the project and construction of underground structures have been carried out safely and economically.