The PILE DRIVING ANALYZER (PDA) is the most employed system for Dynamic Load Testing and Pile Driving.
The dynamic test is recommended by the Brazilian standard NBR 6122 and standardized in Brazil by NBR 13208.
Dynamic monitoring consists in principal of attaching gages to the pile shortly below the pile head, measuring force and acceleration induced in the pile by the hammer impact. The dynamic measurements are collected by a data acquisition unit, the PDA.
The PDA data are usually presented in the form of PDA “wave traces”, which show the measure force and velocity developments drawn against time.
The energy transferred from the hammer to the pile can be determined from PDA data as the integral of force times velocity times impedance.
A double integration of the acceleration produces a displacement trace, displaying the maximum and net penetration of the pile.