Simulation And Analysis Of Crack Propagation In Typical Ship Structure Based On The ABAQUS Software

Defects in materials and structures are unavoidable. Fracture failure of structure induced by defect under low stress is the most important and common failure mode. Fracture mechanics can resolve these problems commendably. However only a very few fracture mechanics problems have analytic solution and most of the time numerical analysis method is needed.This paper simulated crack propagation problems of naval architecture and ocean engineering by using finite element method. First, crack propagation with indeterminate path was discussed. A program package was developed to simulate crack propagation based on ABAQUS using python scripting language. The crack growth in the typical longitudinal connection of Large Nature Gas carrier (LNG) was simulated. Then, for the situation crack path can be presume based on structure and load characteristic, crack propagation was simulated by disposing interface element in the potential crack path. VCCT fracture element and cohesive element was developed and applied to crack propagation in elastic and elastic-plastic material respectively. Finally, in allusion to fatigue crack problems which is familiar to naval architecture and ocean structure, VCCT facture element was extended to fatigue element by inducting fatigue crack extend model. The fatigue element was used to analyze fatigue growth and evaluate fatigue crack propagation life in stiffened panels and simple tank model.The research methods and conclusions of this paper provide a new approach for the analysis of fatigue fracture in naval architecture and ocean engineering field.