DEVELOPMENT OF ELASTIC-PLASTIC INTEGRITY EVALUATION SYSTEM FOR PRESSURE-VESSEL AND PIPINGS

A practically useful system for elastic-plastic fracture mechanics ana lysis has been developed. The developed system is comprised of the J-i ntegral/Tearing modulus (J/T) approach and the deformation plasticity failure assessment diagram (DPFAD) approach. The program contains anal ysis routines for five types of fracture mechanics specimens and five types of flaws in cylindrical geometries. A double and triple interpol ation schemes were adopted to interpolate J values from the EPRI devel oped EPFM handbooks and a material property database was also develope d. Several case studies were performed to evaluate the accuracy and th e usefulness of the code. It was found that the J/T approach and the D PFAD approach yielded similar results. However, the DPFAD approach is more convenient for quick assessment of cracked structures while the J /T approach is more useful in evaluating the full history of the fract ure process.