海上底部出料振冲碎石桩应用

Application of marine bottom-fed vibro-stone column

振冲碎石桩与周围的土体形成复合地基,同时碎石桩作为垂直排水通道,能够加快周围软土的排水固结,是一种快速加固地基、节能环保的地基处理技术。但是由于施工工艺的制约,该方法在软土地基(十字板剪切强度小于20 k Pa的土体)以及限高条件下的应用受到制约。本文以港珠澳大桥香港口岸人工岛项目碎石桩的工程应用为例,介绍一种新型底部出料碎石桩施工工艺,该方法有效地保证了碎石桩在软土地基条件下的成桩质量,同时由于该设备伸缩管等技术的应用,成功减少了设备高度,打破了在机场限高条件下应用的限制。

The stone column and surrounding soil form the composite foundation, and the stone column itself can be taken as the vertical drainage body to accelerate the consolidation of surrounding soft soil. This method can improve ground in a fast and environmentally friendly way. However, because of the restriction of construction method, this method cannot be used in slurry （vane shear strength less than 20 kPa） and in height restriction condition. This article introduces a new bottom-fed vibro-stone column, which forms the stone column in soft foundation with good quality. This method also break the barrier of height restriction of airport by extension tubes to reduce the device height.