Issue 36

Lj. L. Vulićević et alii, Frattura ed Integrità Strutturale, 36 (2016) 46-54; DOI: 10.3221/IGF-ESIS.36.05 54 Based on the obtained values for K Ic for the BM, HAZ and WM, one can conclude that the BM has the lowest resistance to crack initiation and propagation. The fatigue crack simulation for a surface crack in BM, with depth approximately half of the thickness (3.5 vs. 6.98 mm), and initial length 200 mm, indicated 8606 cycles needed for crack to grow through the whole thickness, and 10548 cycles to grow up to the final length of 209.42 mm, i.e. relatively fast growth once it became through-wall crack. R EFERENCES [1] Gubeljak N., Predan J., Kozak D., Leak-Before-Break Analysis of a Pressurizer - Estimation of the Elastic-Plastic Semi-elliptical Through Wall Crack Opening Displacement. Structural Integrity and Life. 12(1) (2012) 31-37. [2] Lazić V.-Lj., Arsić, M., Šarkoćević, Ž., Sedmak, A., Rakin, M., Structural life assessment of oil rig pipes made of API J55 steel by high frequency welding, Technical Gazette, 20(6) (2013) 1091-1094. [3] Belytschko, T., Lu, Y. Y., Gu, I. L., Element-free Galerkin methods, International Journal for Numerical Methods in Engineering, 37 (1994) 229.