Structures and physical properties of soil in shear layr

土的剪切现象经常被观察到，但对其物理性质的研究却很少。本研究的目的是寻找在剪切过程中形成的土体结构，并找出该结构的物理性质。采用箱剪试验对剪切过程中不同阶段含剪切层的土样进行了试验1。对剪切层的结构进行了x射线立体摄影和扫描电镜观察。研究发现，在剪切破坏和蠕变阶段，剪切层是由非常多的小剪切面组成的，这些剪切面像树枝一样链状连接在一起。对剪切层的渗透性进行了测量，发现剪切层的渗透性比未受剪切破坏的土体的渗透性大。3 .土体含水量对抗剪层物理性质的影响土体含水量不同，抗剪强度随含水量的增加而迅速降低。采用h2o气体和N_2气体吸附法测定了各层的空隙体积和比表面积。找出了这些方法在剪切层中的适用条件。

Though shear phenomena of soil are often observed, studies of physical properties of the phenomena are very few. The purposes of this study are to find the soil structures which is formed in the process of shear, and to find physical properties of the structure.Soil samples containning shear layrs at several stages in shear process by box shear tests were tested1.structures of shear layrsX-ray stereoradiographs and scanning electron micrographs were taken. It is found that the shear layrs at the stages of shear failure and creep are formed with very many small shear planes which link together in chains like tree branches.2.Permeability of the shear layrs are measured, and they are larger than that of soil which have not been failed by shear stress.3.influences of soil water content for physical properties of the shear layrsThe structures vary according to water contents, and the shear strength rapidly decrease when water is added.4.void volume and specific surface area of the layrs were measured by H_2O gas and N_2 gas adsorption method. The application conditions of these methods to shear layrs are found.