SAMPLING OF SOFT SOILS IN JAPAN

Sampling methods for marine soft clay in Japan are presented. Two type s of sampling methods are employed in the routine investigation: the c ore tube method and the drilling pipe method. To collect high-quality samples, a thin-wall tube sampler with a fixed piston, whose specifica tion is strictly defined by the Japanese Geotechnical Society, should be used for soft cohesive soils. In addition to the conventional sampl ing method, three newly developed sampling techniques are introduced: the Marine Auto Sampler a wire line-type sampler, and a Laval-type sam pler.