岩溶地区旋挖灌注桩高效成桩工艺研究

Research on High Efficiency Pile Forming Process of Rotary Excavation Cast-in-place Pile in Karst Areas

为了解决岩溶极度发育地区断桩、偏斜、卡钻等成桩效率低的问题,通过对本工程地质条件进行研究,分析旋挖灌注桩施工过程中可能存在的问题,并针对性的提出旋挖灌注桩高效成桩工艺。包括:优化旋挖钻机施工参数防止偏斜卡钻、双护筒钻孔灌注桩施工技术防止土岩交界面坍孔和钻孔注浆填充预处理溶洞施工技术。

In order to solve the low efficiency of pile formation in areas with extremely developed karst,such as pile breakage,deviation,and stuck drilling,the geological conditions of this project were studied,and the possible problems during the construction process of rotary excavation cast-inplace piles were analyzed.In addition,the high efficiency pile formation techniques for rotary excavation cast-in-place piles were proposed purposely,including the optimization of construction parameters of the rotary drilling rig to prevent deviation and sticking of the drill,the construction technology of double casing bored pile to prevent collapse of the soil rock interface,and the construction technology of drilling grouting to fill the pre treated karst cave.