一种特殊土微观结构特性的研究

本文对比较特殊的湛江沿海地区的土样进行了研究,从物理性指标的数值上看,该土的工程性质似较差,其天然含水量为40～45％,孔隙比为1.17～1.28,液限为66％左右等。但从力学性指标来看,其工程性质似较好,其无侧限抗压强度达5～6kg/cm~2,表观先期团结压力达9kg/cm~2。另外,该土风干前后的性质变化明显,液限差14～18％,摩擦角Ф差3～6°。本文中应用了偏光显微镜、扫描电子显微镜和X射线衍射仪分别对试样的组构特征及扁平颗粒的定向排列特征作了观察和测定。并研究了联结组构单元和颗粒单元之间的胶结物质的作用,提出一种结构模式,用以阐述湛江土的某些特殊性质的形成原因。

The Research on Microscopic Structure Properties of a Particular Soil

A sample of a particular soil from Zhan-jiang coastal area is studied. The engineering properties of the soil seem to be poorer from the physical index, its natural water content is 40~45%,void ratio 1.17~1.28 and liquid limit about 66%.But,according to the mechanical index,its engineering properties seem to be better,unconfined pressure strength is about 5~6 kg/cm2, and apparent preconsolidation pressure about 9 kg/cm2. Besides,the properties of this soil before and after it is dried in air have obviously changed,liquid limit decreases by 14~18% and friction angle φ increases by 3~6&;#176;Polarization microscope,scan electronmicroscope and X ray diffractometer are applied separately to view and determine the fabric characteristics and orientated range of flat particles in samples. The bond action of the cement material between fabric and particle units is researched also. A construction model is presented to relate genetical source of some particular nature of Zhan-jiang soil.