Abstract
A practical method of determining strength parameters for stability calculation of landslide slope is proposed in which the strength parameters are given by combining the conventional inverse calculation method, which has been frequently used in engineering practice, with the laboratory shear test results. In addition, the authors have newly developed a fully automated reversal direct box shear (RDBS) test apparatus using a high-precision digital servomotor. Test results on ten kinds of clay samples using the new apparatus are presented. Case studies for three sites of landslide which prove the suitability of design strength parameters determined by using the proposed method based on the test data obtained by newly developed RDBS test apparatus are also presented.
