May 4, 2005

This is a Joint Industry Project (JIP) to develop separate bias factors for evaluation of pile foundations of Gulf of Mexico offshore steel jackets based upon their performance during Hurricane Andrew. Some similarly limited studies will be performed for caisson structures. The purpose is to evaluate possible conservatism in the current American Petroleum Institute (API) RP2A foundation design recipe.

Complete. Results show that the first yield of a pile occurs in three of the cases studied below the respective Hurricane Andrew load levels. The pilehead displacements at first yield are small (3-4 inches) and may be difficult to establish from inspections. Pushover analysis per the 19th Edition of the API recipe indicated a lean angle of less than 5 degrees and pushover analysis per the 20th Edition indicated a lean angle of more than 5 degrees. Assuming that the `acceptable` lean angle is 5 degrees, these results indicate that the metocean criteria for the acceptable damage limit condition lies between the 19th and 20th Edition criteria.

Report

Further Evaluation of Offshore Structures Performance in Hurricane Andrew - Development of Bias Factors for Pile Foundation Capacity (ANDREW FOUNDATION CAPACITY), Final Report submitted by PMB Engineering, Inc., May 1995.