Prediction of Welding Deformation of Hull Panel Blocks Using an Advanced Inherent Strain Analysis Method Considering the Heat Equivalent Layer Effect

초록

When a large-scale structure is fabricated via a complex welding process, deformation and residual stress are challenges that must be resolved. In a thermo-elasto-plastic analysis, calculations are carried out from room temperature through the heating and cooling of the welded joint section where the base metal is melted by the welding heat. It is difficult to apply this type of analysis to large, complex structures due to the prolonged computational time and huge processing volume required. Inherent strain analysis is a more effective approach to analyzing welding strain, and enables the use of an elastic analysis instead of a thermo-elasto-plastic analysis to predict the strain residual stress that occurs in the welded part. This study compares an existing method that analyzes the strain in the welded part by using the correlation between the zone affected by the heat and the adjacent zone constraining the heat-affected zone, and an advanced analysis method that is intended to enhance the accuracy of the results by considering the heat equilibrium zone that exists between the adjacent regions constraining the heat-affected zone. The advanced inherent strain analysis method is applied to obtain more accurate results for a hull panel block model, which is one of the most complex welding structures, by considering a restraint diagram organized according to the welding and fabrication sequence of the members.

키워드