STUDY ON THE STRENGTH OF TYPE B SEMI-MEMBRANE TANK

This is a report on the strength analyses of a semisubmersible tank to determine whether it met the requirements for approval as a Type B tank that are specified in the Gas Carrier Code of the International Maritime Organization (IMO). The authors analyzed a semimembrane tank for a 77,400 cu m LPG carrier. They developed a finite element method program for contact problems involving thin- plate structures such as the tank; used the program to perform a stress analysis; performed fatigue strength and brittle fracture strength analyses; and performed studies on the partial secondary barrier. It was demonstrated that the tank satisfied the IMO Code requirements for a Type B tank. Based on the results and on approvals received, the CLEAN RIVER, the first LPG carrier with Type B semimembrane tanks, was built.