HORIZONTAL BEHAVIOR OF AN EARTHQUAKE-PROOF PILE GUARDED WITH OUTER SHEATH PILE : Part 2 Seismic horizontal capacity of an earthquake-proof pile composed with a PHC-pile and a steel pile

Abstract

This paper continues from the previous thesis (Part 1). It presented experimental result of model earthquake-proof piles guarded with short outer sheath pile and also a calculation method for the pile system of this type. In this study, we calculate the horizontal behavior of earthquake-proof pile composed with a PHC-pile (main pile) and a steel pile (outer pile). It takes into account the non-linear property of bending rigidity of both piles subjected to the vertical load in an earthquake. From these results, it was found that the seismic horizontal capacity of the earthquake-proof pile in both short time and ultimate state could increase remarkably in comparison with an isolated main pile, even if the outer sheath pile length is set up comparatively short.