基于膨润土微观结构确定土水特征曲线的残余含水率

根据蒙脱石层间水化微观结构,建立了蒙脱石水化后的含水率计算公式,并认为蒙脱石发生第1层水化时的含水率即为残余含水率。用4种膨润土土水特征曲线试验数据,分析探讨了考虑不同初始干密度和同一初始干密度下不同温度环境等因素对膨润土土水特征曲线的残余含水率影响。研究结果表明,膨润土的残余含水率与膨润土的比表面积、水膜厚度以及水膜密度成正比,而与膨润土的初始干密度和温度无关。通过实测和计算残余含水率比较,验证了该公式的合理性。

Determination of residual water content in SWCC based on microscopic structure of bentonite

According to the theory of the interlamellar hydration microscopic structure of montmorillonite proposed by Forslind, a formula for calculating the water content of montmorillonite is established after its hydration. When the montmorillonite absorbs only monolayer of water molecules, the water content is considered as the residual water content. The influences of the initial dry density and temperature on the residual water content of bentonite are investigated by using measured soil-water characteristic curves of four different kinds of bentonites. The results show that the residual water content of bentonite is proportional to the specific surface area of bentonite, the thickness and the density of hydrated layer of water molecules, regardless of the initial density and temperature. The comparison between the measured and predicted residual water contents shows that the proposed formula is reasonable.