抄録
The value of c and φ, which are used in analyzing the stability of landslides, can be obtained from poor cohesive soils (“landslide clays”) bearing the shear failure surface of the layers. Most of these clays consist primarily of montmorillonite, which are particularity liable to a slip in the tertiary layer. On the other hand, the value of c and φ depends upon the content of montmorillonite: When theearth has a costant moisture ratio, an increase in the montmorillonite content leads to an increase in the value of c and a decrease of φ.
For this purpose, an X-ray diffraction instrument is used to measure the montmorillonite content.
The methods used in this paper are three kinds: Scale method; Count method; and Area method.