An increasing number of Floating offshore units reach maturity (> 10 years). This induces costly maintenance operations related to hull structure corrosion damage. While crop and renew operations are generally performed in dry docks for supertankers, the FPSO are maintained afloat offshore on the oil field. For obvious security reasons hot work such as welding and gauging are prohibited without a heavy set of recommendations. Naturally, FPSO’s operators have sought “cold” solutions for decades.
This paper describes the specificities of a particular structural bonded reinforcement (ColdShield developed by COLDPAD). A general description of its particularity in the fields of installation and durability is given, but this article is mainly focused on reinforcement strength criterion. Bonded reinforcement strength is known as difficult to predict, making design methodologies not compatible with industrial applications. The innovation in the design of the presented solution leads to a special behavior in terms of strength. It is revealed by the comparison of results of the qualification test campaign with results of tests realized on a standard bonded patch application. Finite element modelling computed parallelly to the tests are used to analyze the test results. The robustness of the reached strength criteria is discussed.