It was found in the book written by Peck R.B. and Hanson W.E (1953) that a driven tapered pile should have greater skin friction than that of a straight-sided pile. The authors have made the study on vertical behavior of a tapered pile installed by the press-in method, and proposed an analytical method based on non-linear Winkler model for the tapered pile. This paper presents the analytical method of a laterally loaded tapered pile considering both of non-linear behaviors of the pile and surrounding soil. On the other hand, the authors made the lateral loading tests on the steel pipe tapered piles in Kanto Loam. This paper also presents the outline of the tests, and comparisons between the lateral displacements and bending moments from the tests and predicted by the method. From the comparisons, it is found out that the predictions are in a fairly good agreement with the test results.
