Abstract
This paper describes the strength obtained from in-situ vane shear test. The undrained strength of vane shear test is formulated based on the elasto-plastic constitutive model proposed by Sekiguchi and Ohta (1977). The stress condition at the failure for the vane shear test used in the formulation are theoretically derived from vertically and horizontally direct-shearing models. Introduced are the effect of shearing rate and anisotropy of vane strength in K0-consolidated clays through comparing the theoretical strength with measured values. And the last part of this paper is devoted to the discussion of the difference between the vane strength and the unconfined compression strength popular in Japan.
