Finite element simulation of drop-weight tear test of API X80 at ductile-brittle transition temperatures

Abstract

This paper proposes a method to simultaneously simulate interacting ductile and cleavage fracture in a DWTT (drop-weight tear test). The stress-modified fracture strain (SMFS) damage model is used to simulate ductile fracture and the maximum principal stress criterion is applied to simulate cleavage fracture. By incorporating the element size effect in the ductile and cleavage damage models, the numerical method to simulate the interacting ductile and cleavage fracture behavior in a DWTT is constructed. To validate the proposed method, the simulation results are compared with six API X80 data measurements at temperatures ranging between -97 degrees C to -20 degrees C. The comparison of the experimental load-displacement curve and fracture surface with the FE simulation results shows good agreement.