软土地基水泥土搅拌桩施工扰动情况现场测试及分析

基于某软土路基水泥土搅拌桩加固工程,设计并进行现场试验来研究水泥土搅拌桩施工过程中对周围土体的影响,测量了施工过程中,周围土体中孔隙水压力和土体位移的变化情况.结果表明:水泥土搅拌桩周围土体的扰动情况与离桩距离、桩到达深度有关;大面积水泥土搅拌桩施工时,孔隙水压力和土体位移都会不断累积增加;泥土搅拌桩由近及远施工比由远及近施工,对周围土体的扰动小;得到最大孔隙水压力增量与打桩点距离之间的拟合关系式.上述结论为软土地区的水泥土搅拌桩的设计和施工优化提供了指导性的意见.

Field Testing and Analysis of Disturbance During the Construction of Cement-soil Mixing Piles in Soft Foundation

Based on a soft subgrade reinforcement engineering using cement-soil mixing piles, a field testing on the influence of the construction of cement-soil mixing piles on surrounding soils is designed. The changes of porewater pressure and displacement of soil during the construction are measured. The results show that： the disturbance is related to the distance and depth between the surrounding soils and piles; when the construction is extensive, the porewater pressure and soil displacement increase will accumulate; the construction of piles have smaller disturbance from near to far than contrary; a fit relationship between the largest porewater pressure increment and distance from piles is obtained. The above conclusions provide an optimization of design and construction for cement-soil mixing piles in soft soil.