Determination of reasonable values of m_v, c_h, c_u/p' for designing embankment foundations on soft clay stabilized by the card-board drain method is described. Model experiments on the foundation failure of partly consolidated clay were conducted and it was observed that their states of failure were very different from homogeneous cases where slip planes of logarithmic arc were clearly observed. A fundamental equation for the consolidation of cylindrical clay with radial drainage is obtained using deformation conditions at the boundary and it is shown that this equation is somewhat different from Barron's.

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This study concerns the effect of the displacement rate on the relation between the horizontal soil reaction and the displacement of sand touching structural elements such as the side of a foundation, basement wall, etc., in case the relative displacement between the soil and the structure is considerably large.The dynamic horizontal soil reactions acting on structures are considered to be affected by many factors. In the present study, simultaneously taken into consideration, are two factors, the number of loading and the depth below the ground surface, in addition to the displacement rate.In the experiments performed by the authors, an extremely rigid pile buried in three kinds of sands was swayed at displacement rates ranging from about 10^-4 cm/sec to about 10² cm/sec. The displacement at the top of the pile and the soil reaction at six points on the pile face, arranged at a depth of 8 cm to 108 cm, were measured.

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The characteristics of decomposed granite soils are, from the point of view of engineering, so unusual that their properties can not be adequately represented by conventional methods such as the unified classification system or the AASHO classification system. In the present paper an attempt is made to apply the authors' classification scheme in which the specific gravity of feldspar indicates the degree of weathering and the amount of coloured minerals is related to the variation of mineral composition.Also presented in the paper is the result of a detailed examination of the effect of cement admixture on the decomposed granite soils.

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