Nonlinear structural modification and nonlinear coupling

Date

2014-06-03

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

218
views

0
downloads

Structural modification methods were proved to be very useful for large structures, especially when modification is local. Although there may be inherent nonlinearities in a structural system in various forms such as clearances, friction and cubic stiffness, most of the structural modification methods are for linear systems. The method proposed in this work is a structural modification/coupling method developed previously, and extended to systems with nonlinear modification and coupling. The method is most useful for large linear structures with nonlinear local modification or coupling. It is based on expressing nonlinear internal force vector in a nonlinear system as a response level dependent "equivalent stiffness matrix" (the so-called "nonlinearity matrix") multiplied by the displacement vector, through quasilinearizing the nonlinearities using describing functions. Once nonlinear internal force vector is expressed as a matrix multiplication form then several structural modification and/or coupling methods can easily be used for nonlinear systems, provided that an iterative solution procedure is employed and convergence is obtained. In the proposed approach the nonlinear FRFs of a modified/ coupled system are calculated from those of the original system and dynamic stiffness matrix of the nonlinear modifying system. Formulations and sample applications of the proposed approach for each of the following cases are given, nonlinear modification of a linear system with and without adding new degrees of freedom, and elastic coupling of a nonlinear subsystem to a main linear system with linear or nonlinear elements. Case studies are given for the verification of the method and then a real life application of the method is presented.

Subject Keywords

Control and Systems Engineering, Signal Processing, Mechanical Engineering, Civil and Structural Engineering, Aerospace Engineering, Computer Science Applications

URI

https://hdl.handle.net/11511/42332

Journal

MECHANICAL SYSTEMS AND SIGNAL PROCESSING

DOI

https://doi.org/10.1016/j.ymssp.2014.01.016

Collections

Department of Mechanical Engineering, Article

Suggestions

OpenMETU
Core

Case study: Planar kinematics of dragline for efficient machine control FRIMPONG, Samuel; Demirel, Nuray (American Society of Civil Engineers (ASCE), 2009-03-24) Overburden excavation is an integral component of the surface mine production chain. In large mines, the walking dragline is a dominant strip mining machine. Dragline performance depends on the operating speed, the bucket payload, and the machine availability, which could be negatively impacted by the actions taken to increase the machine productivity. In this study, the writers develop the kinematics and dynamic modeling of a dragline front-end assembly using the vector loop and simultaneous constraint met...
FINITE-ELEMENT ANALYSIS OF PRESTRESSED AND REINFORCED-CONCRETE STRUCTURES ELMEZAINI, N; CITIPITIOGLU, E (American Society of Civil Engineers (ASCE), 1991-10-01) A practical and powerful technique for the discrete representation of reinforcement in finite element analysis of prestressed and reinforced concrete structures is presented. Isoparametric quadratic and cubic finite elements with movable nodes are developed utilizing a correction technique for mapping distortion. Reinforcing bars and/or prestressing tendons are modeled independently of the concrete mesh. Perfect or no bond as well as any bond-slip model can easily be represented. The procedure is succes...
Die stress and friction behaviour analysis in bolt farming Aygen, Mert; Kılıç, S. Engin; Department of Mechanical Engineering (2006) In cold forming operations, tool geometry has a direct influence on the product quality, forming force, load acting on dies and tool life. Finite element method provides a means to analyse these parameters to predict forming defects and die failures. In this study, shrink fitting the components of a bolt forming die is modelled and the finite element results are compared with the analytical solutions and experiments. In order to perform die stress analyses, deformable die models are implemented in the forgi...
Exact solution of rotating FGM shaft problem in the elastoplastic state of stress Akis, Tolga; Eraslan, Ahmet Nedim (Springer Science and Business Media LLC, 2007-10-01) Plane strain analytical solutions to estimate purely elastic, partially plastic and fully plastic deformation behavior of rotating functionally graded (FGM) hollow shafts are presented. The modulus of elasticity of the shaft material is assumed to vary nonlinearly in the radial direction. Tresca's yield criterion and its associated flow rule are used to formulate three different plastic regions for an ideal plastic material. By considerina different material compositions as well as a wide range of bore radi...
Optimal design of planar and space structures with genetic algorithms Erbatur, F; Hasançebi, Oğuzhan; Tutuncu, I; Kilic, H (Elsevier BV, 2000-03-01) One of the most important practical considerations in the optimization of steel structures is that structural members are generally to be selected from available steel profiles. Furthermore, the solutions produced according to the national specifications are undoubtedly valuable from the point of view of applicability in real-life practice. This paper reports the development of a computer-based systematic approach for discrete optimal design of planar and space structures composed of one-dimensional element...

Citation Formats

T. Kalaycioglu and H. N. Özgüven, “Nonlinear structural modification and nonlinear coupling,” MECHANICAL SYSTEMS AND SIGNAL PROCESSING, pp. 289–306, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42332.