This paper demonstrates the use of the Load and Resistance Factor Design (LRFD) method for design of auger cast-in-place (ACIP) and drilled displacement (DD) piles. The developed method follows a reliability-based design (RBD) and performance-based approach that incorporates a "t-z" model procedure and Latin Hypercube sampling to calibrate LRFD resistance factors. Field load test data from ACIP and DD test piles installed within the same site is integrated within the developed approach to demonstrate a site specific calibration method for resistance factors that satisfy performance-based requirements. The developed method reveals that efficiency and consistency can be achieved simultaneously with safety in the design of these types of deep foundation systems. Copyright ASCE 2009.
