On dual-parameter fracture criterion of welded joints

Based on the existed results of stress field solutions, in the present work a modified dual parameter JQ fracture criterion is proposed for plane strain state, and the criterion may be suitable to both homogeneous material and welded joint. Center cracked welded plate in plane strain condition is selected as a research object. Combined with finite element analysis, discussions are made on the engineering estimate and measurement of the various parameters. The engineering algorithm on the various factors in the fracture criterion is also proposed. Referring to the HRR results, it is indicated that the new criterion can describe stress field nature of homogeneous material and welded joint in plane strain state well. The availability of the new proposed criterion to the homogeneous material and welded joint is discussed. Thereafter, the difficulty of the single parameter J-integral can be overcome, when the modified J-integral parameter is used to describe the stress field intensity of plane strain and weld joint. Thus, the new criterion may be a good basis for engineering evaluation of fracture of welded structures.