沉桩挤土对孔隙水压力影响的试验研究

软粘土层深厚的地区进行预制桩沉桩将产生超静孔隙水压力的累积,过高的超静孔隙水压力使周围土体及建筑、地下管线等产生较大的变位,甚至产生破坏。以一次沉桩引起的超静孔隙水压力的原型试验,表明,单桩沉桩显著影响范围可达15m,沉桩引起的超静孔隙水压力水平可以达到甚至超过上覆有效土压力,并出现两个不同的相对稳定水平阶段。

An In-situ Model Test Study of Excess Pore Pressure due to Pile Driving

Pile driven in thick clayey soil can cause the accumulation of excess pore pressure. The high excess pore pressure can influence soil, buildings and pipes surrounded, even make them injured . In this paper a in - situ model test on excess pore pressure was presented. It was found that the radius of influence range for single pile driven is about 15m, and there were two relatively stable stages, namely local disturbed stage and entirely disturbed stage, corresponding to two inflexions of excess pore pressure level, and the excess pore water pressure can reach or even exceed the above effective soil pressure.