Recently published research presented at this months’ Florida DOT Geotechnical Research in Progress (GRIP) conference further reinforced the revolutionary benefits and potential of the SmartPile™ System. Along with GRIP presentations on post grouting drilled shafts and asphalt recovery were updates on the Embedded Data Collector (EDC), Full Dynamic Testing, and Foundation Resistance Factors. Specific presentations (Titles) included:
- Resistance factors for 100% dynamic testing, w/ & w/o static load tests
- Embedded data collector (EDC) Evaluation phase II – Comparison with instrumented Static Load Tests
which covered further analysis and research in best leveraging the Top and Tip sensor data provided by the EDC. The most exciting elements of this published research work of University of Florida are:
- Accurately determining Static tip resistance: The presented Energy equilibrium method equates applied forces to sum of inertial, damping and static resistance. With measured data from the embedded pile tip accelerometer and strain gauge, an algorithm was developed to calculate damping coefficient and measure static tip resistance in real time. The values were verified against instrumented static load tests performed in Florida and Louisiana. The Measured tip capacity enables engineers and contractors to mobilize only skin friction during redrives instead of the current practice of mobilizing the total pile capacity.
- Accurately determining Static side (skin) resistance: The presented Analytical and numerical methods provide solutions of a one dimensional wave equation of skin friction and damping utilizing the data from the instrumentation embedded at the pile top and tip. The algorithm provides a real time assessment of average skin friction along the pile. The method was validated using the instrumented static load test results in Florida and Louisiana. With this new approach, recognizing the linearity of skin friction with time in semi log domain, contractors and engineers will be able to accurately predict long term freeze using restrike data after a little more than 2 hours. This process can dramatically reduce testing time and mobilization costs as current approaches require redrives days after the original drive to accurately determine Freeze.
- The benefits (higher resistance factor) of additional/full pile testing: The simplified conclusion of the analyses are that resistance factors can be further increased given the lowering uncertainty provided by pile (test) data. The research work provides basis for even higher resistance factors for full dynamic testing (versus the current .75 AASHTO value). A higher resistance factor translates into further driven pile foundation cost savings.
Be warned, these presentations are highly technical, but powerful in their content. All of the conference presentations can be found at:
To Learn More
We continue to add new features and capabilities to the SmartPile System (including the innovations discussed above). To learn more go to www.smartpile.com or contact us directly for more information: firstname.lastname@example.org.
Smart Structures Inc.
324 2nd Street Pike, Unit 13
Southampton, PA 18966