THE PRE-FABRICATED HULL DETAILS FOR APPLICATION IN DESIGN AND REPAIR

This paper discusses how many of structural details such as bracket connections, shell stiffener-transverse web assemblies, etc., are essentially susceptible to fatigue because of the superposition of the stress concentration and the weld endings specific by the feasible weld imperfections and high residual welding stress. In certain applications the fatigue performance of designed and repaired details may be improved in conjunction with the current practice of repair by implementation of the fatigue designed prefabrication details. The principle of the pre-fabricated details is to provide the parent material in the areas of stress concentration and to avoid the coincidence of high stress concentration and weld ending in one location. Transfer of the extensive stress flow via the parent material in modified elements offers essentially better control of fatigue reliability of hull details in design and in service by reducing effects of uncertainties attributed to the production and to the database of fatigue performance of typified welded joints. An application of the local strain approach for evaluation of the necessary configuration of critical locations is also provided.