贵阳地铁车站围护桩施工路面塌陷原因分析及处理措施

Analysis and Treatment Measures of Construction Road Surface Collapse Around Retaining Piles at Guiyang Subway Station

为了查明贵阳地区地铁施工过程中出现的围护桩塌孔、地面沉降开裂等典型工程地质问题的原因,结合场区基本地质条件,采用地质雷达、高密度电法等物探手段,并根据现场开挖揭示的地质进行分析,认为岩土界面上部的软塑状红黏土大量向孔桩内临空面蠕滑以及岩土界面下部的岩溶空腔发生垮塌是主要原因。通过针对岩土界面处软塑状红黏土层实施的高压旋喷桩加固工艺及对比结果,表明该工艺对软塑状红黏土地层加固具有良好的效果。

In order to find out the causes of typical engineering geological problems such as the collapse of the supporting piles and the ground subsidence in Guiyang metro construction,with the combination of the basic geological conditions of the station,geological radar and high density electrical method are applied.According to the analysis of geological profile on the field excavation,it is considered that the soft and red clay sliding greatly into free face of hole pile on the top of the interface and the collapse of karst cavity on the bottom of the interface are the main reasons.By the reinforcement technology of high-pressure jet grouting pile and comparative results,it shows that the technology has a good effect on the reinforcement of soft and red clay soil layer.