Development & application of consolidation apparatus and direct shear apparatus for unsaturated soils

An oedometer and a direct shear device for unsaturated soils were developed. These two apparatuses have several advantages. (1)Load-transducers are set in the air chambers of the equipment. (2)Test data are recorded and are dealt with by a computer. (3)Either vertical pressure or matric suction can be controlled. (4)The gearbox of the direct shear device may provide 15 shear rates. Three groups of direct shear tests and two groups of consolidation tests were conducted, and some characteristics of the deformation and strength as well as water content variation of a undisturbed loess were obtained.