深层搅拌桩处理高速铁路软土地基施工工艺研究

Construction Technique for Deep Mixing Pile to improve Soft soil Ground of High-speed Railway

通过高速铁路软土地基处理现场试验及水泥土室内试验,对深层搅拌桩的施工工艺进行了系统的研究。试验结果表明,采用深层搅拌桩处理高速铁路软土地基是可行的。不同深层搅拌桩机型、相同机型不同机组的成桩强度均存在一定的差异,在进行深层搅拌桩施工时,选择施工队伍与选择机型同样重要。10m复搅和全程复搅、增加复搅次数对桩体无侧限抗压强度影响不大,深层搅拌桩工艺宜采用10m复搅。不同地层对桩体无侧限抗压强度影响较大。浆喷桩桩长在12m以内时,桩体无侧限抗压强度比较均匀,施工质量可控性较高。

The systematic research is done of construction technique for deep mixing pile. The results from the in situ test for improving the soft ground of high-speed railway and indoor test for soil show that the deep mixing pile for improving the soft soil ground of high-speed railway is feasible. For the deep mixing pile completed with different deep mixing pile machine type and the same type of different machine units, its strength is different. During the construction, the construction team selection is just as important as the pile machine type. The 10 m length repeated mixing,full length repeated mixing or the number of increasing repeated mixing have not great influence on its unconfined compression strength. So the technology of 10 m length repeated mixing is suitable to the deep mixing pile. The property of soil has a great influence on the unconfined compression strength. When the grout spray pile is not longer than 12 m, its unconfined compression strength is mean relatively, and the construction quality of the pile can be controlled easily.