Experimental Studies on Strength and Deformation Characteristics of Unsaturated Clay

In this paper, strength and deformation characteristics of unsaturated clays are examined. First, automated triaxial testing system is constructed. The system can automatically measure the data of testing, and record them in the prescribed form. Then, two series of consolidated-undrained shear tests are performed. One is to examine the fundamental properties about unsaturated clay and the other is to examine them about overconsolidated saturated clay to be compared the properties for unsaturated clay. From the results, it is found that there is some similarity between the deformation characteristics of unsaturated clay and that of overconsolidated saturated clay, such as the pore water pressure behavior during undrained shear. But the compressibility of specimen, the strength characteristic and the other characteristics (such as stress-strain relationship and stress path) of unsaturated clays are proved to be quite different from these characteristics of saturated clay