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Title: Simulation of Ductile Fracture Propagation in Structural Steel Subjected to Ultra-Low Cycle Fatigue
While considerable progress has been made in simulating the overall seismic response of steel structures using nonlinear response history (dynamic) analysis, techniques to simulate fracture propagation under large scale inelastic cyclic loading are not as well developed. This is despite the fact that fracture is often a critical limit state that can precipitate structural failure and collapse. To address this, a new ductile damage-based cohesive zone model is presented. The proposed model is an extension of the established continuum-based local or micromechanical ductile fracture models for evaluating ultra-low cycle fatigue in structural steels. This model is implemented in the finite element program WARP3D, and evaluated against tests of notched bars that fail by ductile crack propagation. The preliminary results indicate that the model is an effective tool for predicting ductile fracture initiation and propagation in structural steels subjected to monotonic and cyclic large scale inelastic loading. Implications of this for characterizing the post-fracture response of structural steel components are discussed, along with limitations of the research.
Authors:
; ; ; ; ;
Award ID(s):
1635043
Publication Date:
NSF-PAR ID:
10079310
Journal Name:
Eleventh U.S. National Conference on Earthquake Engineering
Sponsoring Org:
National Science Foundation
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