Ship Structure Committee Publishes Reports On Fatigue Curves And Underwater Repair Procedures

The Ship Structure Committee has recently issued two new reports on the following topics: Reduction of S-N Curves for Ship Structural Details, and Underwater Repair Procedures for Ship Hulls (Fatigue and Ductility of Underwater Wet Welds). Report SSC-369 "Reduction of S-N Curves for Ship Structural Details" presents a set of fatigue S-N curves for design and analysis of ship structural details. The set of fatigue curves is based on a re-analysis of fatigue data presented in the Committee's SSC-318 report. The methodology used to develop the fatigue SN curves is presented. Examples are presented to illustrate the application of S-N curves for plating under one-inch thick. A glossary of terms used is provided and recommendations are presented for future research. Report SSC- 370 details the use of underwater welding for the repair of damage below the waterline of a ship or marine structure. These procedures have developed greatly in recent years. However, these procedures have generally only been acceptable as emergency repairs and temporary. Uncertainties with regard to the long term properties of the repairs have prevented a greater acceptance. This report addresses specifically the fatigue performance and low tensile elongation properties of underwater wet weld repair methods. The report concludes with recommendations for future research. These reports, and any other SSC report, may be ordered from National Technical Information Service, Springfield, Va. 22151, tel: (703) 487-4650; fax: (703) 321-8547.

For report SSC-369 ask for accession number PB94-121928; for report SSC-370 ask for accession number PB94-121936.