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Augered Cast-in-Place (ACIP) piles have seen a rapid increase in demand. Factors such as high shaft resistance to volume-of-concrete ratio and fast, vibration-free installation with low noise, makes the ACIP pile a desirable deep foundation alternative. A variety of pile installation techniques exist that range from the typical hollow-stem augered ACIP pile to partial or full displacement pile. However, ACIP piles present challenges associated with as-built shape, structural integrity and relatively high load bearing capacity demands. Therefore, load testing techniques that increase reliability of load capacity determination are critical. In this paper, advances in the dynamic load testing techniques as applied to ACIP piles are presented. New techniques include the use of top transducers, the use of embedded instrumentation and testing recommendations specifically for ACIP piles. Top transducers speed up and facilitate load testing and increase the accuracy of top force measurement readings. Embedded instrumentation, particularly near the pile toe, helps improve the accuracy of pile wave speed assessment and calculated resistance distribution. Testing recommendations include the necessary hammer energy for optimal permanent penetrations per blow, which completely activate pile resistance while limiting over-prediction of ACIP bearing capacity in plastic soils. Additionally, a correlation between dynamic load test and static load test results recently performed on 47 ACIP piles tested in North and South America ranging from 16 to 30 inches in diameter is presented. Finally, supplemental testing and analysis techniques for further improvement of testing reliability and performance of ACIP piles are proposed, such as thermal integrity profiling and signal matching of the data from embedded sensors when available.

High capacity of rock-socketed or end bearing drilled shafts is often not fully exploited due to the highly conservative design that many local codes and local practices around United States dictate. This reduces the cost efficiency of drilled shafts versus other foundation solutions. ADSC is interested in developing a test program procedure that will be economically feasible for engineers and foundation contractors to perform in every project even when load tests are not specified. Static load tests (including conventional top-down and bi-directional load tests) are invaluable but often prohibitive due to high cost and time constraints. Alternatively, high strain dynamic testing of drilled shafts has increased significantly in recent years with well-established testing procedures and analyses. More specifically, ADSC is considering using dynamic load testing to prove the high capacities of drilled shafts in several rock formations around the country and establish limits of extrapolation to larger diameter shafts from tests on smaller diameter shafts. The purpose of this paper is to present the theoretical basis of ADSC's technical endeavor. More specifically the paper will focus into 2 different topics; i) parameters affecting drilled shaft performance and ii) the theory and principals of dynamic testing as applied to rock socketed drilled shafts, as well as, case studies of dynamic tests in rock socketed drilled shafts.

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