Test-based Fracture Criteria for Pipeline Steels

Steel pipelines as key Canadian infrastructure are often exposed to various geological and environmental conditions that cause defects such as cracks, dents, and gouges in the pipe wall, which can lead to pipe fracture in pipelines, compromising the entire pipeline's functionality and resulting in significant economic losses, environmental issues or even fatalities. There are several methods to predict the fracture capacity, including experimental testing, analytical approaches, and advanced numerical methods. The use of fixed fracture strain criterion implemented in the computer programs may not appropriately predict the crack propagation path because of the concentration of large strains. Further, fracture criteria that ignore the crack tip constraints and depend on the type of the test specimens used to obtain fracture indices may lead to inconsistent predictions. There is a need to develop and implement more efficient and accurate fracture criteria specific to pipe steel as a function of crack tip constraints, independent of the type of specimens used and the size of pre-cracking. This research project aims at developing calibrated numerical-based fracture criteria for predicting the crack propagation in steel pipelines.

Amr Mohamadien
Faculty Supervisor: 
Ali Imanpour;Samer Adeeb;Yong Li
Partner University: