FITNESS-FOR-SERVICE DESIGN FOR UNDERWATER WET WELDS

This paper presents a new concept of improving the use of wet welds fo r underwater Structure repair or construction. A flexible intermediate connection pad, prefabricated on land and welded to the structural me mbers in wet condition, cushions the stresses on joints. The inherentl y inferior impact property of the wet weldment can be coped with prope r design of this cushion pad. The wet welded joint can therefore fit i ts designed purpose. In this study, both design analysis and experimen tal tests were conducted to demonstrate the design solution using the cushion pad. A statistical data base on wet weld properties was first developed to define the performance level of wet welds. The fitness fo r service of the flexible connection was evaluated by impact testing. The results show that the performance level of the connection can be i mproved through proper design regardless of the low toughness of the w et weldment.