A node release approach to estimate J-R curve for single- edge-notched tension specimen under reversed loading

摘要

This paper proposes a node release approach to estimate the fracture resistance curve, often known as the J-R curve, for monotonic and cyclic fracture tests. The node release approach simulates the crack extension by releasing the constraints imposed on the node at the crack tip and estimates the J-R curve by coupling the domain integral value with the corresponding crack extension. This proposed node release approach estimates closely the J-R curve for SE(B) and SE(T) specimens subjected to monotonic loading. For SE(T) specimen under cyclic loading, this study implements the node release analysis in two approaches: (1) an equivalent monotonic analysis corresponding to the envelope of the cyclic load-CMOD response and (2) a direct cyclic simulation. Both approaches lead to close estimations of the experimentally measured J-R curve. The numerical analysis also confirms the path independence of the domain integral values in the direct cyclic simulation.