High Strain Dynamic Pile Testing
High Strain Dynamic Pile Test
The Pile Driving Analyzer (PDA) is the most widely employed system for Dynamic Load Testing and Pile Driving Monitoring in the world. It assesses the capacity of several piles in a single day. The PDA also evaluates shaft integrity and investigates driving stresses and hammer energy during pile installation. The test shall conform to ASTM D4945-17.
The driving hammer itself is used to perform PDA tests, or High Strain Dynamic Test, on pilot or production piles. If necessary, it is possible to perform re-strike PDA tests even after the driving hammer is no longer on location, by using a drop weight to impact the foundation.
The PDA calculates results from velocity and force signals obtained by sensors (accelerometers and strain transducers) attached to the pile.
CAPWAP (CAse Pile Wave Analysis Program) is a software program that estimates total bearing capacity of a pile or shaft, as well as resistance distribution along the shaft and at the toe. The program takes as input the force and velocity data obtained with a Pile Driving Analyzer (PDA).
It is essential to post process PDA data with CAPWAP for at least one foundation element per job. CAPWAP completes the Dynamic Load Testing procedure and simulates a Static Load Test.
The program includes a completely automated mode as well as adjustable parameters with which the user systematically improves the calculated results. Extensive correlations between CAPWAP simulated and actual static load tests have proven the reliability of this method of determining pile capacity.