Abstract
The purpose of this research is to clarify the evaluation of the bearing capacity of a pile with multi-stepped two diameters. Model tests were conducted by driving multi-stepped type metallic piles into two kinds of dry ground to evaluate the bearing mechanism. The following points about the pile with multi-stepped two diameters were confirmed; i) for the bearing capacity of the convex part, the failure mechanism is classified into two categories depending on difference in the concave part length, and ii) the normal pressure on the shear surface around concave parts is bigger due to the bearing effect of the convex part. Quantitatively, the procedure used the spherical cavity expansion method offers potential for better prediction of the pile with the long concave part. Considering the bearing effect on the base of the convex part, another procedure could be good predictions for shear resistance around the short concave part in the sand ground.
