Abstract:
High strain dynamic load testing or simply dynamic load testing (DLT) has been routinely used for decades to evaluate the static bearing capacity of deep foundation elements (driven piles, drilled shafts, auger-cast piles, etc.). In addition to bearing capacity prediction, inspection of the upward travelling wave (Wave-Up) provides engineers a powerful tool to evaluate pile integrity and geotechnical concerns with these foundation elements. Most technologies created by Engineers take decades to refine, as the core of capable data collectors, case studies, and pool of industry experts grow. DLT data interpretation is certainly no exception, and historically, through the natural process of this practice maturing, various norms were generally established by advanced practitioners, that soon became broader consensus.The authors have observed that this consensus in certain nuances of the field have manifested themselves into what can be considered "technical dogma,†disseminated by practitioners now of all experience levels. Areas reviewed in this study include how the practitioners often apply some apparent engineering norms to adjust or interpret raw data, and how to later apply the now standardized signal matching parameters to accomplish the DLT's ultimate goals. Though there has been extensive research and commentary on wave-up interpretation, some of these widely accepted misconceptions in data adjustment, signal matching, and general wave-up interpretation have not been clearly clarified. Based on rich experiences monitoring thousands of piles with DLT, the authors present some lessons learned from various case histories to challenge general consensus in typical areas of data analysis and interpretation.