真空预压法加固机理分析  

Analysis of Vacuum Consolidation's Mechanism

作　　者：汪令松[1] 周怀民[2] 齐永正[3] 

机构地区：[1]马钢(集团)控股有限公司办公室,安徽马鞍山243000 [2]中建八局基础设施建设有限公司,上海200000 [3]江苏省交通科学研究院,江苏南京210000

出　　处：《安徽冶金科技职业学院学报》2009年第2期41-44,51,共5页Journal of Anhui Vocational College of Metallurgy and Technology

摘　　要：真空预压法的传统观念认为真空预压加固软土地基中总应力是恒定不变的,在土体中产生负的超静孔隙水压应力。通过分析传统观念的矛盾之处,指出矛盾的产生是由于假设总应力不变而引起的,进而推导出在真空预压加固软土地基中总应力是变化的,在土体中产生的是正的孔隙水压力,真空预压法和堆载预压法有效应力增长值均是孔隙中超静孔隙水压应力消散而产生的孔压差值。从应力路径与变形的关系方面,说明了真空预压法是等向均匀体积收缩,加固区外土体产生主动土压力,土体呈拉裂破坏。The traditional idea supposes that vacuum- assisted consolidation preloads the soil by reducing the pore pressure while maintaining a constant total stress. But in this paper, author points out that vacuum consolidation increases the effective stress in the soil mass by increasing the total stress and the positive pore water pressure is caused in the soil mass as well. Like in the case of a conventional surcharge, in the case of vacuum surcharge, the total stress will increase due to the additional load and thus, the effective stress will increase as well. This paper illustrates that vacuum consolidation is even volume shrinkage from the relation of stress path and deformation. Soil mass out of consolidation generates passive pressure, and thus, clay presents split.

关 键 词：真空预压 加固机理 总应力 孔隙水压应力 应力路径 

分 类 号：TU472.33[建筑科学—结构工程]