Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Conference Object Citation - Scopus: 1Strength Requirements of Permanent Metal Deck Forms Used for Lateral Bracing of Steel Bridge Girders(2006) Eğilmez, Oğuz Özgür; Helwig, T.A.; Herman, R.S.Permanent metal deck forms (PMDF) are often used in steel bridges to support the weight of the wet concrete during deck construction. Although the PMDF also has the potential to provide bracing to steel bridge girders during construction, the stiffness of the PMDF system as a lateral brace is drastically reduced by the eccentric support angle connection detail used to attach the forms to the girders. Laboratory tests have shown that a simple modification to the connection detail can substantially increase the stiffness of these PMDF systems and allow utilization of the PMDF for girder bracing. This paper presents results from a parametrical study conducted to determine stability and strength requirements for PMDF used to provide lateral bracing to steel bridge girders. Detailed FEA models were used to determine the stability bracing strength requirements for the fasteners that are used to connect the PMDF along the sidelaps of the sheets and to the girders. Design expressions are presented as well as an example demonstrating the use of the design equations.Book Part Citation - Scopus: 2Computation Time Efficient Stiffness Analysis of the Modified R-Cube Mechanism(Springer, 2019) Görgülü, İbrahimcan; Dede, Mehmet İsmet CanParallel manipulators are known to be more stiff than the serial manipulators. However, modeling the stiffness for parallel manipulators are difficult compared to serial manipulators due to the constrained structure and passive joints. In addition, computation of the stiffness model for parallel manipulators are exhausting since it requires an iterative solution algorithm due requirement of force-position convergence of all serial chains connecting to the same mobile platform. Direct solutions are faster however, they lack in accuracy. In this study, direct solution is preferred for real-time application and analytic stiffness model of the modified R-CUBE mechanism is obtained by using Virtual Joint Method (VJM). The finite element (FE) model is constructed and simulated to validate the analytical model. Then, a combination of external wrenches $$\pm 5$$ N in various directions are applied on the mobile platform in both FE and VJM in some critical poses. Finally, the computed numerical results are listed and compared along with their computation times. © Springer Nature Switzerland AG 2019Conference Object Citation - Scopus: 1Structural Compliance Effects on the Accuracy and Safety of a R-Cube Haptic Device(Springer Verlag, 2019) Carbone, Giuseppe; Acinapura, Antonio; Mundo, Domenico; Görgülü, İbrahimcan; Dede, Mehmet İsmet CanThis paper addresses the contribution of structural compliance on stiffness and safety of a R-CUBE Haptic Device. Structural compliance is determined in several poses via FEM analysis and addressed by referring to local and global indices of performance. Results are also compared with evidences from experimental tests. Comparison of numerical and experimental data allows to identify and separate the contributions to the overall compliance that are due to the structural stiffness, and other contributions such as joint clearance, pose and loading conditions.Conference Object Citation - Scopus: 2A Critical Review of Unpowered Performance Metrics of Impedance-Type Haptic Devices(Springer Verlag, 2019) Görgülü, İbrahimcan; Kiper, Gökhan; Dede, Mehmet İsmet CanA kinesthetic haptic device’s performance relies on unpowered, powered and controlled system characteristics. In this paper, a critical review is carried out for the well-known metrics for kinematics, stiffness and dynamic aspects of robots that can be applied in evaluating the unpowered system performance of kinesthetic haptic devices. The physical meanings of these metrics are discussed and the important factors that affect the unpowered system performance of a kinesthetic haptic device are revealed.Conference Object Citation - Scopus: 1Stiffness and Strength of Shear Diaphragms Used for Stability Bracing of Slender Beams(Curran Associates, 2014) Eğilmez, Oğuz Özgür; Akbaba, Andaç; Vardaroğlu, MustafaLight gage metal decking is often used in structures as concrete deck formwork, roof cladding or siding. In the steel building and bridge industries, decking acts like a shear diaphragm and provides continuous lateral bracing to the top flange of non-composite beams and girders that they are attached to. The building industry has long relied on the in-plane stiffness and strength of metal decking to brace steel beams during construction. Although the current AASHTO LRFD specifications do not allow bridge deck forms to be relied upon as a bracing source for steel bridge I-girders, recent studies have demonstrated that deck forms can significantly increase the buckling capacity of bridge girders by providing a relatively simple modification to the connection. Shear diaphragm bracing of steel I-beams have been studied in the past. These studies mainly focused on beams with stocky webs. The purpose of the study outlined in this paper is to enhance the understanding of both the stiffness and strength of shear diaphragms used to brace slender steel I-beams. The parameters that are investigated include diaphragm stiffness, sheet thickness, number of side-lap fasteners, flange width, and web slenderness ratio. Beams with web slenderness ratios of 100 to 160 and span/depth ratios of 10, 15, and 20 are considered. A simple finite element analytical (FEA) model is utilized in the study. The results indicate that web slenderness ratio does not have a major effect on fastener forces and the strength behavior of shear diaphragms is dependent on the number of side-lap fasteners. The findings of the study will be used to develop strength and stiffness requirements for shear diaphragms used to brace slender steel beams