沉桩挤土效应的软土微结构时效特征

Aging Characteristics of the Soft Soil Microstructure of Pile Driving Soil Squeezing Effect

采用水平向压缩试验模拟静压桩挤土过程，借助扫描电镜记录挤土过程中软土微观结构变化，通过土的微观结构定量参数分析，找出软土微结构在压缩固结过程中随时间的变化规律，并将微结构的变化过程划分为两个阶段，即前期振荡阶段和后期趋稳阶段。模拟试验的结果，对采取工程措施减少或避免挤土效应具有指导意义。

The process of static pressure pile squeezing is simulated through compression horizon- tal experiment. With the aid of scan electron microscopy, record the microstructure changing of soft soil in the process of squeezing. By analyzing the quantitative parameter of soil microstructure, find out the changing rule of soft soil microstructure with time in the course of compression and consolidation, and divide this changing process into two phases that are prophase vibration and anaphase vibration. The re- sult of this simulation testing has guiding meaning for reducing or avoiding squeezing effect by adopting project measures.