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This work describes a method in which the digital image correlation (DIC) method and finite element analysis (FEA) were used to create a quasi-static mixed-mode fracture envelope for bonded joints consisting of 2024-T3 Al adherends and a tough structural epoxy adhesive. Symmetric and asymmetric versions of double cantilever beam, single-leg bend, and end-notched flexure tests are used to populate the mixed-mode fracture envelope with results at several mode mixities. Experiments are conducted in a universal testing machine while recording images for subsequent DIC analysis. Finite element analysis is used to implement cohesive zone models (CZMs) of the adhesive fracture and to account for plastic deformation of adherends. Mode I and mode II traction separation laws (TSLs) are determined from a property identification method with a Benzeggagh–Kenane mixed-mode coupling law used to model mixed-mode behavior. FEA results are shown to provide a good agreement to both the crosshead displacement and DIC data. The methods in this paper serve as a potential framework for future calibration of mixed-mode fracture envelopes for joints bonded with very tough adhesives that complicate assessment with traditional data analysis methods.
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Spine Specimen 2:Subtitle
Specimen 2 was created to combat some of the issues found from the static testing of Specimen 2. The base dimension was increased from 1.5” to 2”. The width of the cantilever was also decreased to increase the flexibility of the element. Static testing of Specimen 2 revealed that the element flexibility was increased to achieve a stiffness of 83 k/in resulting in larger post-yielding deformation. Yielding occurred in the cantilever area only.
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- Award ID(s):
- 1926326
- PAR ID:
- 10653818
- Publisher / Repository:
- Designsafe-CI
- Date Published:
- Edition / Version:
- 1
- Subject(s) / Keyword(s):
- force-limiting connection spine FLC steel frame-spine lateral force-resisting system
- Format(s):
- Medium: X
- Location:
- Bethlehem PA
- Institution:
- Lehigh University
- Sponsoring Org:
- National Science Foundation
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