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Indexed by:期刊论文

Date of Publication:2018-12-01

Journal:ENGINEERING FRACTURE MECHANICS

Included Journals:SCIE、Scopus

Volume:204

Page Number:268-287

ISSN No.:0013-7944

Key Words:Phase field model; Cohesive fracture; Iteration scheme; Abaqus; UEL

Abstract:Recently, phase field modelling of fracture has gained much attentions because of its benefits in predicting cracks initiation and propagation without any ad-hoc criterion. In the model cracks are smeared into the surrounding areas by introducing an auxiliary crack phase field which should be solved either by iteration or using sufficiently small loading increment, and this makes the method be computationally demanding. The introduction of other complex models e.g. cohesive zone model results in nonlinear damage sub-problems which may further increase the number of iteration steps. In this study, an improved staggered iteration scheme by which the nonlinear sub-problems are solved by a one-pass procedure is proposed. Such that the computational costs can be reduced and the stability of iteration can be improved. In particular, a unified phase field model which integrates varies cohesive relationships is investigated. The phase field model as well as the iteration scheme are implemented through Abaqus subroutine UEL (user defined element). The present study is validated through comparing both of crack propagation path and load-displacement curve with existing results. Moreover, comparisons on total iteration steps and the elapsed total computational time are made between the proposed iteration scheme and the existing scheme, and the results demonstrate that the proposed iteration scheme is very suitable for the considered problem.