真空渗流场的形成机理探讨

软基在“真空预压”法处理过程中的固结,不是因其所谓的“真空荷载”进行“预压”所致,而是因“真空渗流场”的形成并在其作用下产生“渗透固结”所致。全文详细探讨了“真空渗流场”的形成机理,包括该场中孔隙水运动的物理模型和土体固结的物理模型。在对土体固结模型探讨的过程中,首次将“有效应力”的概念扩展成“竖直向”有效应力和“水平向”有效应力两种,并在此基础上提出了“双弹簧固结模型”。从有效应力发展过程的角度探讨“真空渗流场”的形成过程时,发现该模型能较好地符合“真空预压”对软基的作用实质。

Research on the Forming Mechanism of Vacuum Seepage Field

In the course of treating soft foundation by "vacuum preloading", the consolidation of soft foundation is not brought about by the "pre-pressing" of "vacuum load", but by the formation of vacuum seepage field and the "infiltrating-concretion" caused by vacuum seepage field. In the paper, the forming mechanism of vacuum seepage field is discussed in detail, including the physical models of pore water moving and soil consolidating. In the discussion of the soil consolidation model, the "effective stress" is expanded into two parts, which are the vertical effective stress and the horizontal effective stress. Based on this, a bi-spring consolidation model has been put forward. By analyzing the forming process of the vacuum seepage field from the aspect of the "effective stresses" developing, the bi-spring consolidation model is found to fit the essential of the effect of "vacuum preloading" on soft foundation.