A Procedure for a Strength Assessment of Permanent Means of Access Structure

Abstract Common structural rule (CSR) doesn’t provide any other specific regulations for permanent means of access (PMA) platform structure in a cargo oil tank. The PMA platform is recommended to comply with scantling requirement of local su pport member. However, it leads to too conservative scantlings compared with actual lo ads imposed on the platform. This paper proposes a strength assessment procedure for the PMA structure based on a nonlinear ultimate strength. The ultimate strength is evaluated in a sufficiently conservative way. The first linear buckling mode is used as an initial imperfection shape and its magnitude is determined using the definitions of DNV PULS. Sinc e the same imperfection mode as the failure mode of the ultimate limit state is assumed , it can accelerate the failure. Au ultimate strength capacity curve obtained from a series of nonlinear FE analysis is compared with actual stresses calculated by CSR cargo hold analysis. ※Keywords: Permanent means of access, Common structural rule, N onlinear FE analysis(비선형 유한요소 해석), Ultimate strength analysis(최종 강도해석) 접수일: 2008년12월 26일, 승인일: 2009년 2월 2일 g교신저자: beomseon.jang@samsung.com, g교신저자: 02-3458-7658