非饱和粉土中模型支盘桩在重复荷载作用下的试验研究

设计了一个室内模型试验装置来研究支盘桩的承载和变形性能,对一个双盘模型支盘桩进行了5次循环加载–卸载的试验。通过对所采集的有关数据的研究,分析了该桩荷载传递的特点、桩身不同位置压力变化的特点和原因,特别是上、下两盘之间的土体对桩侧表面产生的摩擦力在不同条件下会出现正负的变化;分析了离盘不同距离的土体在每次加载过程中的压力变化情况,证明每次加卸载后桩周土体会建立起新的工作状态,直到多次重复后达到稳定。最后对如何合理设计支盘桩的桩距、盘间距来保证其工作性能提出了建议。

Model tests on piles with branches and plates in unsaturated silt under cyclic loads

A model test equipment was designed to study the beating capacity and deformation behavior of the piles with branches and plates. Five cycles of circulating load on the model pile with two plates were done. By studying the collected data, the load transfer behavior, the characteristic and the variation of pressure on piles were analyzed, especially the case that the skin friction of the silt between the plates was positive or negative under different conditions. The variation of soil pressure around plates under each loading was also analyzed. It was proved that after each loading and unading of silt a new state would be established until a stable state was reached. At last it was suggested how to design the spaces of piles and plates to assure ,the performance of piles.