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A hybrid structural stress method is presented for significantly simplifying spot weld representations in fatigue evaluation of complex spot-welded structures while retaining a high degree of accuracy in structural stress computation. The method is formulated by extracting nodal forces and moments around a group of domain elements connected to a spot weld represented by a regular beam element. Through a systematic decomposition technique, existing closed-form solutions, previously only valid for modeling single-spot weld test specimens, can now be used for calculating the relevant structural stresses under complex loading conditions in structures, as validated its ability in correlating fatigue test data.
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Fracture Mechanics Modeling of Fatigue Behaviors of Adhesive-Bonded Aluminum Alloy Components
Adhesive-bonding has become increasingly adopted for multi-material lightweight applications (e.g., automotive structures). There is a growing interest in understanding the fatigue behaviors in this type of joint for supporting structural durability modeling in practice. In this paper, an analytical fracture mechanics modeling procedure is presented in the context of a generalized sandwich specimen. Its closed form stress intensity factor solutions were then derived and applied for the correlating fatigue test data obtained from the lap-shear and coach-peel test specimens with demonstrated effectiveness. Some important implications of these analytical solutions on joint design are also discussed.
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- Award ID(s):
- 2126163
- PAR ID:
- 10359208
- Date Published:
- Journal Name:
- Metals
- Volume:
- 12
- Issue:
- 8
- ISSN:
- 2075-4701
- Page Range / eLocation ID:
- 1298
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/met12081298
