粘土固结参数变化的分析

本文依据土力学中已建立的基本概念,通过试验研究,首先找出正常固结粘土的渗透系数K与孔隙比e的关系,压缩系数a_V与孔隙比e或有效固结压力σ′的关系,从而推导出固结系数C_V与孔隙比或有效固结压力的关系表达式。分析不同土类固结系数的变化,归纳出三种典型的情况,即:C_V随e的减小而减小;C_V随e的减小而增大和C_V基本上与e无关。并指出特殊土类的C_V有特殊的变化规律。其次,分析了固结指数m变化的物理依据,讨论了m值与有效固结压力和上层厚度H的关系,最后,说明C_V和m变化的相互关系以及实用计算中应注意的问题。

Analysis of Varation of Clay Consolidation Parameters

Based on the fundamental conception soil mechanics, by experimental research, the relation of the coefficient of permeability K to the void ratio e and that of the coefficient of compression aγ to the effective consolidation pressureσ’ are first expressed for normally consolidation clays. Hences the expression of relation of the consolidation coefficient cν to the void ratio e or the effective consolidation pressures is given. There are three typical cases of variation of the consolidation coefficient for different soils types, i.e. the value Cν decreases with the void ratio’s decrease; the value Cν increases with the void ratio’s decrease and the value Cν is essentially independent of the void ratio. Specific variation of the value Cν for specifically soil type is pointed out. The physical foundation for the variation of consolidation index m is explained. The relationships between the value m, the effective consolidation pressure σ’ and the soil layer thickness H are discussed. Finally, correlation between the value Cν and m’s variation as well as the noteworthy problems in practice are represented.