Strength of thick-sheeted welded structures of ships and marine structures in the Arctic

Abstract

Object and purpose of research: This paper studies thick-sheeted welded structures of marine technology operating at the temperatures of -40°С and lower. Current regulations of classification societies regarding fracture resistance of welded joints for these structures are usually impossible to meet for a number of technological and economic reasons, which, if regarded formalistically, might result in prohibition of operation at low temperatures. The purpose of this work is to develop an alternative approach to ensuring strength (cold resistance) of welded structures based on the newly-developed method of direct static strength calculation for welded structures, with consideration of really achievable fracture resistance and plasticity parameters of the welded joint material. Materials and methods: The strength calculation method suggested in this paper implies FEM-based procedures in combination with strength verification methods for steel structures, as per the criteria of brittle failure and ultimate plastic straining. Main results: The paper suggests a new verification calculation method for the static low-temperature strength of ship structures, and also suggests the alterations in the system of regulations regarding fracture resistance and strength at low temperatures for the thick-walled structures operating in the Arctic. Conclusion: The method developed in this work will ensure trouble-free operation and operational safety of the structures applied aboard Arctic ships and marine structures. This method is the basis for the new technology that will allow development of structures at lower costs.

Keywords

• fractures
• strength
• Arctic
• welded structures
• marine structures
• temperature conditions