考虑真空负压沿排水板的衰减分布对排水板周围土体固结特性的影响,开展室内模型试验模拟某一深度处预压地基排水体中真空负压对其周围土体径向固结的过程。通过分析排水板周边土体基本物理力学性质、渗透性、压缩性及土颗分的时空分布特点,研究不同真空负压强度对排水板周围土体径向固结的影响。试验结果表明随着真空度沿着排水体的衰减,排水板对周围土体的影响范围逐渐缩小,在软基深部有大面积的交叉影响区,对软基浅部优于深部;细微颗粒在真空负压差作用下发生向着排水板方向运移并,使得在排水板周围细颗粒含量增大,远端细微颗粒减少;基于真空渗流场理论,结合颗分试验结果,分析了真空预压过程中细颗粒运移成因,进一步解释了“土桩”形成机理。 Considering the effect of vacuum negative pressure distribution along the drainage board on the consolidation behavior of soil around the drainage board, indoor model test was conducted to simulate the radial consolidation of the surrounding soil under the vacuum drainage of the pre-stressed foundation drainage body at a certain depth process. The effects of different vacuum negative pressure on the radial consolidation of soil around the drainage board were studied by analyzing the basic physical and mechanical properties, permeability, compressibility and soil-temporal distribution of soil around the drainage board. The experimental results show that as the degree of vacuum decay along the drainage body, the influence range of the drainage board on the surrounding soil is gradually reduced. There is a large area of ​​cross-impact zone in the deep soft foundation, which is superior to the shallow depth of soft foundation. Under the action of vacuum pressure difference, the migration towards the drainage board takes place and the content of fine particles around the drainage board increases and the fine particles on the far side decrease. Based on the theory of vacuum seepage field and the results of particle test, the vacuum preloading process The reason for the fine grain migration, further explains the formation mechanism of “soil pile ”.