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attributed to loss of load carrying capacity of the individual members. Dominant failure modes in structural steel members include interactions between inelastic lateral torsional buckling, global buckling, and local buckling (referred to as Interactive Buckling). Accurate performance assessment of steel moment frames highly relies on the accuracy of the model-based simulations of such limit states. Commonly used concentrated hinge and fiber-based models fail to address the physics of this response leading to inaccurate performance assessment of structures. A nonlinear displacement-based fiber element [named Torsional Fiber Element (TFE)] to simulate monotonic and cyclic interactive buckling in steel members is proposed and implemented on OpenSees (an open-source finite element software). The element includes St. Venant as well as warping torsion response that are essential for lateral torsional buckling response in a wide-flange I-section, through enriched displacement fields and strain interpolation. Response of local buckling is represented in a quantitative manner using a novel multi-axial constitutive relationship with calibration of an effective softening behavior in the post-buckling response. Mesh dependency issue related to the softening material model is also discussed and addressed through a proposed non-local strain measure. The efficacy of the model is assessed through several continuum finite element simulations and experimental data.
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Prediction of thermally induced postbuckling of clutch disks using the finite element method
Buckling and postbuckling of automotive clutch disks can be excited by the temperature fields caused by frictional heat generation during engagement of clutch systems. Linear and nonlinear buckling finite element analyses are performed to evaluate the thermal postbuckling of clutch metal disks. The dominant buckling modes are first obtained through performing linear buckling finite element analysis (FEA) analyses. The scaled displacement fields obtained from the linear buckling FEA analyses are added to the original geometries to generate the perturbed meshes. The postbuckling is then investigated by performing nonlinear buckling FEA analyses. The commercial FEA software ABAQUS is used in the current study. The effects of the temperature-dependent material properties are studied. It is concluded that the temperature dependence of material properties affects the postbuckling behaviors significantly.
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- Award ID(s):
- 1928876
- PAR ID:
- 10465175
- Date Published:
- Journal Name:
- Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology
- Volume:
- 235
- Issue:
- 2
- ISSN:
- 1350-6501
- Page Range / eLocation ID:
- 303 to 314
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1177/1350650120901978
