排水粉喷桩软基加固技术应用研究

Application of Dry Jet Mixing Pile with Vertical Drain in Soft Foundation Reinforcement

排水粉喷桩复合地基法是一种新型的软基加固方法,该法利用粉喷桩施工时产生的侧向压力和竖向排水通道,加速土体中孔隙水的排出,以达到快速加固软土地基的目的。结合工程实际,运用Plaxis有限元软件对工法进行了数值模拟研究,发现排水粉喷桩复合地基法的沉降主要发生在排水固结区,且呈向下和向外逐渐减小的趋势,粉喷桩桩土应力比在1.8左右,孔隙水压力呈先增长后逐渐消散的过程。

Dry mixing pile with vertical drain is a new reinforcement method for soft foundation,which uses lateral pressure produced during dry mixing pile construction and vertical drainage channel to accelerate the drainage of pore water in soil mass for rapid reinforcement of soft foundation.In this paper,this method is numerically simulated using Plaxis finite element software combined with engineering practice.It is found that the settlement of composite foundation reinforced by dry mixing pile with vertical drain mainly occurs in drainage consolidation area,with the trend of gradual decrease downward and outward.Pile-soil stress ratio of dry jet mixing pile is about 1.8.Pore water pressure first increased and then gradually dissipated.