Use of Explosives to Enhance Power of a New Design of Pile Hammer

The purpose of this paper is to describe the adaptation of conventional concepts of internal ballistics to the driving of piles. Special considerations are given to the differentiation between the usual solution for guns, in which a lightweight projectile is propelled at a very high velocity, and a pile driving hammer propelling a ram with a relatively low velocity. The basic premise of a high explosive hammer is introduced, and a scheme is suggested for obtaining a pressure-space relationship for the propellant chamber and the velocity of a movable ram, comprising the base of the chamber, at the time it impacts a pile. The feasibility of using such a hammer to drive an offshore deep penetration pile in a deposit of clay is investigated by means of wave equation modeling.