通过归纳分析发现,适用于描述常压条件下黏土压缩特性的扩散双电层理论和不平行板模型均不能对高压条件饱和黏土的双线性压缩特性进行解释.将黏土的孔隙划分为团聚体间、颗粒间及颗粒板内三层面可很好地对饱和黏土的高压压缩过程进行定性描述:高压条件下,除团聚体间及板间扩散双电层两部分的自由水分子的排出外,晶层间规则排列的结合水分子也将被逐层挤出.而该小间距条件下,基于扩散双电层机制的理论解释已不再适用,且由于水分子与晶层间的特殊结合,其他Non-DLVO作用力的出现亦必须重新加以考虑.基于此,提出了从理论上利用格子密度泛函理论描述黏土矿物界面外水分子的特殊结合形态,并嵌入该格子模型于分子动力模型中,从分子尺度研究高压条件下水-界面间的相互作用,从而最终建立基于分子层面黏土高压压缩本构关系的新思路.%Based on the summary and analysis of the theories and models which were adequate to interpret the compressibility of saturated clay under low stress, such as diffuse double layer theory and nonparallel plate model, it was found that these theory or model failed to describe the bilinear shape of compression curves under high pressure. In order to facilitate a qualitative description of the complete compression process of clay, the total pore volume was classified into three different structural levels,which were called macropore,micropore and interlayer pore respectively. Under high pressure, apart from the expulsion of the free water enmeshed inside the aggregates and particles, the organized water molecules that adsorbed on the crystals were also be squeezed out layer by layer. And when two surfaces or particles approached closer to a few nanometers, continuum theories of attractive van der Waals and repulsive double-layer forces often failed to describe these interactions;other Non-DLVO forces came into play. Therefore,a new thought of study on the compressibility of saturated clay under high to has been proposed in the last part of this paper. By describing the specific arrangement of water molecules around the clay miner with the lattice density functional theory and conducting steered molecular dynamics simulation, the constitutive relation of saturated clay under high pressurerncould be constructed on the basis of molecular scale.
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