Wave-in-deck forces on offshore platforms

The extreme condition storm wave crest heights for many older platforms indicate that there would be green water'' in the lower decks. The API guidelines to determine wave forces acting on the decks of these platforms indicate that most platforms cannot survive such loadings. The decks must either be removed or the decks raised to cleat the specified wave crests. A variety of laboratory tests have been performed to address this problem. Several approaches have been developed to compute the wave crest loadings and the responses of the platforms to the loadings. There have been many instances in which platforms have experienced significant wave loadings in their lower decks during hurricanes. Some of these platforms have survived and some have failed. This paper summarizes results front a study of laboratory test results and the performance of platforms in the Gulf of Mexico that have survived and failed during hurricane wave loadings in their decks. Modifications to the API deck wave force guidelines are discussed and validated with laboratory test data and platform field performance during hurricanes.