Performance of Pile Driving Hammers

Using results from both theory and measurements the action and behavior of hammer-pile systems are considered. Three types of models are used to describe the behavior of a hammer-pile system. One is the wave solution of St. Venant for a pile struck by a rigid body. The two other models use a mass and a spring to describe the effects of blocks and cushions, respectively. The interpretation of measured quantities using such models allows conclusions to be drawn regarding the driving ability of a hammer, situations involving pile damage, energy losses and transfer and characteristics of certain measured quantities. As a result it is shown that the Michigan records were meaningful within the particular measuring system used and recommendations are given for a transducer design that allows the measurement of more meaningful quantities. Diesel hammer performance and energy output is analyzed and it is shown that these hammers perform adequately.