Comparison of J resistance curves from toughness testing specimens with those from various cracked pipe tests

J contour integral still has great importance to predict fracture of both small specimen and full-scaled pipes. However, it is difficult to obtain experimental J resistance curve of full-scaled pipes due to the differences of defect shape and complexity of loads. Due to the recent development of the FE damage analysis to predict fracture of full-scaled pipes, it is also possible to predict J resistance of full-scaled pipes. To use this FE damage model for fracture estimation, it is necessary to verify the validity of this model by compared with toughness testing specimens. In this paper, J resistance curves of full-scaled pipes using FE damage analysis were compared with various toughness testing specimens from Pipe Fracture Encyclopedia performed by Battelle. And the J contour integral were calculated from FE analysis using the element-size-dependent damage model recently proposed by the authors. Compared results showed that J calculation using FE damage analysis could be used for J-estimation of full-scaled pipes by compared with fracture toughness testing specimens.