土工基础

›› 2014, Vol. 28 ›› Issue (3): 73-75.

• 工程实录 • 上一篇    下一篇

真空-堆载预压法膜下真空度变化规律研究

徐平波1，李成磊2   

  1. (1.中交四航工程研究院有限公司，广州〓510220；2.中国建筑第二工程局有限公司深圳分公司，广东深圳〓518005)
  • 收稿日期:2013-08-11 出版日期:2014-06-20 发布日期:2014-06-28
  • 作者简介:徐平波（1987-），男，硕士，助理工程师，研究方向为岩土工程地基处理。

Degree of Vacuum Change in a Vacuum Preloading with Surcharge Project

XU Pingbo1, LI Chenglei2   

  1. （1.CCCC Fourth Harbor Engineering Institute Co., Ltd. Guangzhou 510220；
    2.China Construction Second Engineering Division Corp. (Shenzhen), Shenzhen 518005）
  • Received:2013-08-11 Online:2014-06-20 Published:2014-06-28

摘要： 运用真空-堆载预压法处理饱和淤泥质土地基时，膜内真空度大小以及土层真空度的法向传递直接决定了淤泥土的固结时间以及固结效果。通过对真空堆载预压的微观机理分析并结合实际工程实例，讨论了真空度沿土层变化规律以及影响土层中真空度变化规律的相关因素。研究表明，真空度沿土层的法向传递是气体分子由高密度区向低密度区的运动过程，淤泥质介质对气体分子运动的粘滞性强烈，能量损失严重，土层以下20m处已没有真空度，真空预压效果已不存在，而地下水位线以下真空度是由水位线下降引起的。

关键词: 真空-堆载预压, 真空度, 传递规律, 影响因素

Abstract: When using the vacuum preloading with surcharge method to improve the saturated peaty soils, the degree of vacuum underneath the membrane and its vertical delivering into the deeper layer are critical to the duration of the preloading and the result of the soil improvement. This paper presents a case history of using this method from the microscopic point of view. The degree of vacuum change with soil depth and factors that affecting the degree of vacuum in the soil are analyzed. It is concluded that the degree of vacuum change in the soil is a process of air particles moving from high density areas to low density areas. The peaty soil media has a strong damping effect to the air particles and the energy dissipation in this soil is strong. Under 20 meters below the ground, the degree of vacuum cannot be detected. The vacuum formed below the ground water line is formed by lowering the ground water table.

Key words: Vacuum-Preloading with Surcharge, Degree of Vacuum, Vacuum Transfer, Influence Factors