软土中静压桩挤土效应的模型试验研究

Study on Model Experiment of Squeezing Effects of Jacked Piles in Soft Clay

通过大型模型箱试验,采用盐城地区典型场地软土,分别以单桩和排桩为研究对象,研究了沉入单桩和排桩过程中的挤土效应,比较分析了沉入单桩和排桩时土体变形和孔隙水压力的变化规律。试验结果表明,径向距离愈大,挤土效应的影响愈小,沉入单桩时挤土效应对位移和孔隙水压力的影响范围在0.6倍和0.5倍桩长左右,沉入排桩时,挤土效应对位移和孔隙水压力的影响范围在1倍桩长左右和超过0.7倍桩长。试验结果对软土地区桩基工程的施工具有指导意义。

Based on large-scale model box experiment, using soft clay of typical sites in Yancheng District and taking the single pile and row piles as the study objects respectively, the squeezing effects with the process of sinking into the single pile and row piles are studied, and the variation law of the soil deformation and pore water pressure is compared and analyzed while sinking into the single pile and row piles. The results shows that the greater the radial distance, the smaller the squeezing effects; the influence scope of soil compaction on the displacement and pore water pressure reaches 50 to 60 percent the pile length sinking the single pile, and after sinking row piles, the influence scope on the displacement and pore water pressure is about 100 percent the pile length and more than 70 percent the pile length. The results could guide the pile foundation construction in soft soil.