Worldwide Calibration of API RP2A‐LRFD

Abstract

API RP2A‐LRFD (load and resistance factor design) has recently been approved by the American Petroleum Institute for the design of fixed offshore steel platforms. It is an alternative to the more familiar working stress version of RP2A, which has been used worldwide for many years; outside of American waters regional modifications are often applied. Through the load and resistance factors, the LRFD approach offers even greater opportunity to reflect regional differences in environmental conditions and design and operating practices. This paper describes the work undertaken to adapt LRFD for use in the North Sea. Sets of load factors have been calibrated for the in‐place design conditions to suit the North Sea climate and U.K. design practices using a reliability‐based calibration procedure. An alternative set of resistance factors for tubular joints have also been assessed, which lead to more consistent reliability.