Ultimate strength formulation considering failure mode interactions of ring-stiffened cylinders subjected to hydrostatic pressure. (1st August 2018)

• Record Type: Journal Article
• Authors: Cho, Sang-Rai; Muttaqie, Teguh; Do, Quang Thang; So, Ha Young; Sohn, Jung-Min
• Is Part Of: Ocean engineering. Volume 161(2018)
• Page Start: 242
• Page End: 256
• Publication Date: 2018-08-01
• Subjects: Ring-stiffened cylinder -- Ultimate strength formulation -- Collapse pressure -- Failure mode; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2018.04.083
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: This paper outlines empirical formulas to provide adequate predictions of the ultimate strength of ring-stiffened cylinders under hydrostatic pressure. The ultimate strength formulation was derived from published test data found in the open literature. The formulas consider the failure mode interactions, which include the parameter of shell yielding, inter-frame buckling, overall buckling, and stiffener tripping. The failure modes were inserted in the quadratic Merchant-Rankine formula. Afterward, the knockdown factors were empirically derived to best fit the actual collapse pressure. It is found that the proposed formulation can predict the ultimate strengths of ring-stiffened cylinders more accurately and consistently than other codified rules (PD5500, GL, ABS, API). The simple criterion for the assessment of failure modes was also provided. Furthermore, parametric studies were conducted to observe the effect of the design parameter on sizing the ring-stiffened cylinder when the failure modes can be predicted. Highlights: A ultimate strength formulation considering the failure mode interactions has been derived and proposed. The prediction accuracies of the proposed formulation are substantiated with 107 test results. A semi-analytical tool has affirmed to differentiate the distinctive failure mode. The effects of the design parameters for sizing the ring-stiffened cylinder are reviewed.