Key Aspects for LRFD Implementation of Driven Pile Capacity by Dynamic Methods

摘要

Inputs and interpretation procedures for pile wave equation analysis, which correlates measured field dynamic driving response to axial pile static capacity, are highly dependent on site-specific soil conditions and field practices. The 6th Edition of the AASHTO LRFD Bridge Design Specifications provide generalized guidelines for pile design, but do not account for variability in region-specific soils and field practices. A comprehensive literature review of region-specific resistance factor recalibration efforts across the U.S. has given insight into the range of implementation issues encountered, especially the key decisions around choosing a restrike (BOR), along with measures of efficiency and treatment of time-dependent capacity gain through pile set-up for BOR. A reevaluation and statistical exploration of cases within the extensive Portland State University (PSU) Pile Load Test Database offers special insight into the implementation issues for the PSU recalibration effort specific to Oregon Department of Transportation (ODOT) and Pacific Northwest Practice. The information gathered from this research provides a general commentary on increased foundation reliability and guidance for approaches to implementation of LRFD bridge pile foundation design into practice.