摘要
深层渗滤效应普遍存在于多孔介质的渗透注浆过程中,并起着非常重要的作用。基于质量守恒方程、线性滤过定律、渗流连续性方程及Darcy定律,建立了水泥浆三维锋面的理论模型;通过现场试验,研究了水泥浆三维锋面扩散运移及沉积层渗透系数的变化规律,并将试验值与模型理论值进行了对比分析。结果表明,沉积层渗透系数随水泥浆锋面的扩散运移动态变化;当注浆压力恒定时,水灰比越小,深层渗滤效应越显著,浆液扩散距离相应越短;相同扩散距离时,受重力效应的影响,注浆点源之上的沉积层渗透系数大于注浆点源之下的沉积层渗透系数;浆液扩散距离及固定位置处的沉积层渗透系数均与水灰比呈正相关。研究成果可指导工程设计,具有一定的实际应用价值。
Deep filtration effect widely exists and plays an important role in the process of permeation grouting in porous media. Based on the mass conservation equation, linear filtration law and seepage continuity equation as well as Darcy law, a theoretical model is developed for three-dimensional slurry frontal surface. The migration of the slurry frontal surface migration and the variation of the permeability coefficient of the deposition layer are examined based on in-situ grouting test; the measured values are compared with the theoretical ones. It is shown that the permeability coefficient varies as the frontal surface migration. At the constant grouting pressure, the deep filtration effect is more significant, and the slurry diffusion distance is shorter when the water-cement ratio is smaller. At the same diffusion distance, the permeability coefficient of the deposit layer above grouting point source is larger than that below the grouting point source, due to the influence of gravity effect. The grouting diffusion distance and the permeability coefficient of the deposit layer at a specified point are positively correlated with the water cement ratio. The above result has practical bearing, in which it can help construction designs.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2015年第11期3171-3179,共9页
Rock and Soil Mechanics
基金
国家自然科学青年基金(No.51309146)
山东大学自主创新基金(No.2012GN011)~~
关键词
多孔介质
深层渗滤效应
渗透注浆
运移机制
渗透系数
porous medium
deep filtration effect
permeation grouting
migration mechanism
permeability coefficient
