Interface Damping At Riveted Joints. Part I - Theoretical Analysis
Report Number: ASD TR 61-467 Part I
Author(s): Mead, D. J., Eaton, D. C. G.
Corporate Author(s): Southampton Univ (United Kingdom)
Laboratory: Directorate of Materials and Processes
Date of Publication: 1961-09
Pages: 41
Contract: AF 61(052)-332
DoD Project: 7351 - Metallic Materials
DoD Task: 73521 - Behavior of Metals
Identifier: AD0270463
Abstract:
In this paper a theoretical examination is made of potential structural damping increments that could be obtained by insertion of a linear visco-elastic interfacial layer between plates of riveted joints. Consideration is given to a lap joint having anti-symmetry about its single rivet, and being subjected to harmonic longitudinal loading. Certain simplifying assumptions have been which effectively reduce the analysis to a one dimensional system. An expression is obtained for the energy dissipated in the layer per cycle of load. The magnitude of this energy dissipation has been computed for a wide range of joint dimensions, dynamic properties of the layer, and rivet stiffnesses. It has been found that as the thickness (or shear modulus) of the layer is varied, a maximum value of the energy dissipation occurs. The conditions for this maximum are examined, and a simple design rule is established whereby the maximum damping may be achieved in a joint using a given material. It is shown that the elastic deformation of the plates has a significant effect only when high values of rivet stiffness the energy dissipation may be found to a sufficient degree of accuracy by neglecting altogether the plate flexibility.
Provenance: Lockheed Martin Missiles & Fire Control
Author(s): Mead, D. J., Eaton, D. C. G.
Corporate Author(s): Southampton Univ (United Kingdom)
Laboratory: Directorate of Materials and Processes
Date of Publication: 1961-09
Pages: 41
Contract: AF 61(052)-332
DoD Project: 7351 - Metallic Materials
DoD Task: 73521 - Behavior of Metals
Identifier: AD0270463
Abstract:
In this paper a theoretical examination is made of potential structural damping increments that could be obtained by insertion of a linear visco-elastic interfacial layer between plates of riveted joints. Consideration is given to a lap joint having anti-symmetry about its single rivet, and being subjected to harmonic longitudinal loading. Certain simplifying assumptions have been which effectively reduce the analysis to a one dimensional system. An expression is obtained for the energy dissipated in the layer per cycle of load. The magnitude of this energy dissipation has been computed for a wide range of joint dimensions, dynamic properties of the layer, and rivet stiffnesses. It has been found that as the thickness (or shear modulus) of the layer is varied, a maximum value of the energy dissipation occurs. The conditions for this maximum are examined, and a simple design rule is established whereby the maximum damping may be achieved in a joint using a given material. It is shown that the elastic deformation of the plates has a significant effect only when high values of rivet stiffness the energy dissipation may be found to a sufficient degree of accuracy by neglecting altogether the plate flexibility.
Provenance: Lockheed Martin Missiles & Fire Control