抄録
The dispersion in the characteristics of adjacent ground is examined based on the several cone penetration tests. It is shown that (1) N-values in the same stratum vary due to the small shift in the depth of the hard and soft points, and are in good agreement if the depth is corrected; (2) Althought the coefficient of variation from the all measured data is large, the mean value coefficient from certain range of depth is comparatively small; (3) It is conclude that the coefficient of variation used for a pile skin friction has to be selected based on the mean values within a certain range of depth.
