Comparison of Axial Resistance of Driven Piles Determined Using Automatic Signal Matching Software, iCAP and CAPWAP: Fid-Bau Portal

Comparison of Axial Resistance of Driven Piles Determined Using Automatic Signal Matching Software, iCAP and CAPWAP

Steward, Eric J. / Jones, Ronald / Rausche, Frank

For years, the Alabama Department of Transportation (ALDOT) has been collecting dynamic testing data during pile installation and restrikes to estimate the pile axial resistance of driven piles at the end-of-initial-driving (EOID) as well as at various time periods after EOID. Traditionally, this dynamic testing information is analyzed using a signal matching software CAPWAP designed to provide more accurate results of the axial resistances of the installed piles. The CAPWAP signal matching software can be time-consuming and requires a trained engineer to perform the analysis. A new, faster version of the CAPWAP software, called iCAP, is now available that performs the signal matching analysis of the dynamic data automatically, i.e., without operator interaction. The iCAP software calculates the pile bearing capacity without relying on an assumed soil damping factor and, therefore, can be used to determine the Jc damping factor for the simplified case method. The ALDOT provided acquired dynamic testing data for 25 test piles installed throughout the state of Alabama for analysis to determine the feasibility and reliability of using the iCAP signal matching software for pile driving projects. A comparison of the signal matching analysis of 74 unique blows of both concrete and H-Pile pile testing data is performed to determine the accuracy and reliability of the iCAP results compared to the CAPWAP results. The results show a reliable comparison between the iCAP and CAPWAP analysis for all piles in various soil types within the state of Alabama.