Penetration Resistance for Driven Piling

Procedures for estimating penetration resistance for driven piling are proposed and investigated. Each method is analyzed by comparison of predictions and field observation on five projects. Estimated pile bearing capacity based on soil properties and on pile driving records is used as the basis of the predictions. Wave equation analysis, the Hiley equation, and the Engineering News formula are all considered as means of estimating penetration resistance from bearing capacity. The validity of the predictions is shown to improve with increasing quality of the procedures for analysis of pile dynamics. It is also shown that for sites where pile driving records are available, penetration resistance estimates can be very reliably made. The records are first converted to driving resistance (dynamic capacity) using a dynamic formula. The driving resistance curves are then converted to penetration resistance with a dynamic formula and characteristics of the hammer proposed for use.