The Federal Highway Administration (FHWA) mandated the use of the Load and Resistance Factor Design (LRFD) method in the U.S. for all new bridges initiated after October 1, 2007. Presented in this paper are selected results from a recent nationwide survey that has focused on the current design and construction practices of bridge deep foundations. The specific topics targeted in the study were current foundation practice, pile analysis and design, pile drivability, design verification, and quality control. The responses obtained from more than 30 State Department of Transportations (DOTs) revealed that a) more than 50% of the state DOTs are currently using LRFD method for pile design, while 30% of the DOTs are still in transition from Allowable Stress Method (ASD) to LRFD method, and b) about 35% of the DOTs that employ the LRFD for piles utilize regionally calibrated resistance factors to improve the cost-effectiveness of pile foundations.
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