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Simulating the Clamped Tapered Beam Specimen Under Quasi-Static and Fatigue Loading Using Floating Node MethodAs part of the NASA Advanced Composites Project (ACP), a sub-element has been designed to provide validation data for progressive damage analysis models. The clamped tapered beam is a cross-ply laminated composite specimen designed to validate the simulation of the onset of matrix cracks and their interaction with delaminations, including delamination migration. A tapered geometry was used to localize the first damage occurrence in the tapered region, without prescribing an initial crack. The boundary and loading conditions were chosen to favor delamination growth and subsequent migration after the first damage occurrence. The typical sequence of events consists of a matrix crack located at the tapered region, leading to delamination onset, followed by delamination growth and subsequent delamination migration to a different interface via a dominant matrix crack. The Clamped Tapered Beam (CTB) was tested in both quasi-static and fatigue regimes. The results obtained are used in this study to assess and validate a methodology based on the Floating Node Method (FNM) implemented as an Extended Interface Element. In this methodology, quasi-static and fatigue damage formation and development are modeled by combining FNM to represent crack networks, with Directional Cohesive Zone Elements (DCZE) and Virtual Crack Closure Technique (VCCT), respectively. Qualitatively, the methodology is capable of predicting the sequence of events and overall failure morphology. Quantitatively, the simulation results generally bound the experimental data, based on the range of the characterization data used. In this paper, the results from quasi static and fatigue simulations are compared and correlated with experimental data.
Document ID
20180006193
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Authors
Seshadri, B. R.
(National Inst. of Aerospace Hampton, VA, United States)
de Carvalho, N. V.
(National Inst. of Aerospace Hampton, VA, United States)
Ratcliffe, J. G.
(NASA Langley Research Center Hampton, VA, United States)
Mabson, Gerald E.
(Boeing Co. Seattle, WA, United States)
Deobald, Lyle
(Boeing Co. Seattle, WA, United States)
Date Acquired
October 9, 2018
Publication Date
January 8, 2018
Subject Category
Structural Mechanics
Report/Patent Number
NF1676L-27492
Meeting Information
Meeting: AIAA SciTech
Location: Kissimmee, FL
Country: United States
Start Date: January 8, 2018
End Date: January 12, 2018
Sponsors: American Inst. of Aeronautics and Astronautics
Funding Number(s)
CONTRACT_GRANT: NNL09AA00A
WBS: WBS 826611.04.07.01
Distribution Limits
Public
Copyright
Public Use Permitted.
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