某变电站地基为新近回填的松散状粉细砂,设计采用灰土挤密桩处理方案,施工采用锤击沉管工艺。在施工之初及过程中出现了塌孔及达不到预定深度等问题,为此,分别增加了夯扩桩管内夯击施工和短螺旋排土成孔夯实工艺。三种方法间隔跳打的联合施工措施,有效地解决了施工难题。经检测,复合地基承载力等各项指标均达到了设计要求。 The ground of a substation is newly refilled loose silt, which is designed with lime-soil compaction piles. The construction is carried out by hammering immersion pipe. At the beginning of the construction and during the process, collapse holes and up to a predetermined depth were encountered. To this end, they increased the ramming construction in the compacted and expanded pile pipe and the short screw-trenching and soil forming compaction process respectively. Three methods of interval hopping joint construction measures, effectively solve the construction problems. After testing, bearing capacity of composite foundations and other indicators have reached the design requirements.