FINITE ELEMENT SIMULATION OF CLEAVAGE FRACTURE PROPAGATION IN PIPELINE STEELS USING XFEM-COHESIVE SEGMENT TECHNIQUE

摘要

The main objective of this study is to predict cleavage fracture behavior of API X70 CO_2 pipeline steels by means of numerical modelling. To do so, eXtended Finite Element Method (XFEM)-based cohesive segment technique is used to model lab-scale Drop Weight Tear Test (DWTT) of X70 pipeline steel at -100°C. In this model dynamic stress intensity factor and crack velocity are calculated at crack tip at each step of crack propagation. From the simulation results, it was found that the proposed approach can be a suitable methodology to model cleavage fracture behavior of pipeline steels.