Vibration analysis of structures using substructure synthesis

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Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Mechanical Engineering, Turkey

Approval Date: 1989

Thesis Language: English

Student: NADİR ÇETİNKAYA

Supervisor: HASAN NEVZAT ÖZGÜVEN

Abstract:

VIBRATION ANALYSIS OF STRUCTURES BY USING SUBSTRUCTURE SYNTHESIS ÇETÎNKAYA, Nadir Faculty of Engineering Mechanical Engineering Department, fcLSc. Thesis Supervisor: AssocProfDr. HJîevzat ÖZGÜVEN Co-Supervisor: AssocProfDr. Mehmet ÇALIŞKAN 154 Pages, February 1989 ABSTRACT In this study, substructure synthesis methods developed for vibration analysis of large and complex structures are studied. The basic techniques used in the development of substructure synthesis concept are overviewed, and the use of Rayleigh-Ritz approach in substmcturing techniques is investigated. A computer program for free vibration analysis of structures by substructure synthesis method with dynamic condensation and Guyan reduction is improved incorporating Rayleigh-Ritz approach in substructure synthesis method. Several trial vectors obtained by discretizüıg orthogonal jRmctions like Chebyshev polynomials, Hermite polynomials, Lagüerre polynomials and trigonometric amotions are used in the Rayleigh-Ritz approach. mThe computer program prepared is used to demonstrate the accuracy and the speed of the new approach. Different orthogonal functions are employed in the analysis of beam and plate bending problems. The eflects of number of Rits vectors and number of substructures on the accuracy of natural frequencies and the computation times are also investigated. Key Words; Structural dynamics. Finite element method, Substructure synthesis, Rsyieigh-Rits method, Guyan reduction, Dynamic condensation, Eigenvalue problem. IV