Harmonic Response of Large Engineering Structures with Nonlinear Modifications

Date

2011-07-06

Author

Kalaycioglu, Taner
Özgüven, Hasan Nevzat

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

197
views

0
downloads

In a structural design, the structure may need to be modified and for each modification its dynamic characteristics may need to be determined by reanalyzing the structure dynamically. Since computational time and cost are very critical in design processes, structural modification methods become decisive, particularly for large systems, in predicting the dynamic behavior of modified structures from those of the original and modifying structures. Due to nonlinearity in most engineering structures, linearity assumption may not be applicable to all cases. Then, well known structural modification methods can not be directly used, and it is required to employ a nonlinear structural modification method. In this paper, a structural modification/coupling method proposed in an earlier study is extended for nonlinear modification/coupling. The nonlinearities are quasilinearised using describing function method, and thus nonlinear internal force vector is expressed in terms of a response-dependent matrix which can be regarded as a response level dependent "equivalent stiffness matrix", called "nonlinearity matrix". Then the method developed for linear structural modification/coupling is employed by using an iterative solution procedure. Three case studies are presented in this paper. In the first case study, a nonlinear test structure used in an earlier study is employed and the frequency responses of the system at different forcing levels are calculated by using the approach suggested. Then they are compared with experimental results. Secondly, a simple discrete system is analyzed to demonstrate the accuracy of the approach proposed. Lastly, a large scale model is considered to illustrate the applicability of the approach proposed to large order systems.

Subject Keywords

Structural modification, Nonlinear structural modification, Vibration of nonlinear structures, Nonlinear structural coupling

URI

https://hdl.handle.net/11511/55255

Conference Name

8th International Conference on Structural Dynamics (EURODYN)

Collections

Department of Mechanical Engineering, Conference / Seminar

Suggestions

OpenMETU
Core

Structural Coupling of Two Nonlinear Structures Tepe, Çağrı; Ciğeroğlu, Ender (null; 2015-02-02) In mechanical design, modeling and analysis of a complex structure can be simplified with dividing the structure into substructures; therefore, any change in the structure can be addressed easily which is referred as “structural coupling”. Utilization of proper coupling techniques, it is possible to understand the behavior of the whole structure by considering the behavior of its substructures. For linear structures, coupling is a common technique; however, in most of the engineering structures, nonlinearit...
Structural coupling of two nonlinear structures Tepe, Çağrı; Ciğeroğlu, Ender; Department of Mechanical Engineering (2018) In mechanical design, modelling and analysis of a complex structure can be simplified with dividing the structure into substructures; therefore, any change in the structure can be addressed easily which is referred as “structural coupling”. Utilization of proper coupling techniques, it is possible to understand the behavior of the whole structure by considering the behavior of its substructures. For linear structures, coupling is a common technique; however, in most of the engineering structures, nonlineari...
Nonlinear Structural Coupling: Experimental Application Kalaycioglu, Taner; Özgüven, Hasan Nevzat (2014-02-06) In this work, the nonlinear structural modification/coupling technique proposed recently by the authors is applied to a test system in order to study the applicability of the method to real structures. The technique is based on calculating the frequency response functions of a modified system from those of the original system and the dynamic stiffness matrix of the nonlinear modifying part. The modification can also be in the form of coupling a nonlinear system to the original system. The test system used i...
Harmonic response of large engineering structures with nonlinear modifications Kalaycıoğlu, Taner; Özgüven, Hasan Nevzat; Department of Mechanical Engineering (2011) During the design and development stages of mechanical structures, after each modification made in order to satisfy design criteria, dynamic characteristics of the structure change and should be determined through reanalyzing the structure dynamically. Due to the significance of computational time and cost in design processes, it is inevitable for structural modification methods, especially for large systems, to become involved in predicting the dynamic behavior of modified structures from those of the orig...
Prediction of geotechnical properties of cohesive soils from in-situ test : an evaluation of a local database Yaman, Gökhan; Erol, Orhan; Department of Civil Engineering (2007) In any geotechnical design procedure, the fundemantal point to be initially clearified is the characterization of existing soil profile at a site. This requires a great deal of planning a suitable site investigation program including borings, sampling, laboratory and in situ testing etc. Laboratory and in-situ (field) tests are important tools leading to the estimation of soils properties in geotechnics. Beside laboratory tests, the measurement of engineering properties in situ is a continuously growing and...

Citation Formats

T. Kalaycioglu and H. N. Özgüven, “Harmonic Response of Large Engineering Structures with Nonlinear Modifications,” presented at the 8th International Conference on Structural Dynamics (EURODYN), Leuven, BELGIUM, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/55255.