Nonlinear reduced order modeling of bolted joints

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2019
Karapıstık, Gökhan
Most of the structural systems assembled by using bolted joints. Therefore, bolted joint models have a critical importance to estimate the behavior of the overall assembled system. There are several linear bolted joint models, which consist of spring and dashpot elements in literature. While they can estimate the resonant frequency of the overall system with a sufficient accuracy, linear bolted joint models are inadequate for approximating the damping, which arises from the friction in the contact interface of assembled system. On the other hand, there are examples of nonlinear bolted joint models, which utilize 3D contact models to account for the frictional damping behavior in the literature. However, modeling the structures with many bolted joints by using high fidelity 3D contact models is very time consuming. Therefore, reduced order bolted joint models with sufficient accuracy are in need. In this thesis, a method for modeling bolted joints in frequency domain is introduced. The joint model consists of microslip friction elements each one of which is constructed by several dry friction elements in parallel and located at the contact interface.

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Citation Formats
G. Karapıstık, “Nonlinear reduced order modeling of bolted joints,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.