this paper presents an overview of model updating and particularly its application for updating of frame model. in this article a mathematical model of the frame was produced with finite element method. the frame was subjected to hammer modal testing. then the results of the modal testing were compared with those predicted with the model. this comparison revealed discrepancies between these two...

During the past few decades, a significant amount of research has been conducted in the area of non-destructive damage evaluation (NDE) based on changes in dynamic properties of a structure. System Identification and damage detection plays a crucial role in structural dynamics and vibro-acoustic system optimization. The later approach is based on the ‘Modal Analysis” The dynamic behaviors of th...

Copyright © 2003 by GTSJ Manuscript Received on July 7, 2003 ABSTRACT Asymmetric rotors or shafts with dissimilar moments of area form a special category of rotor dynamics problems. Of specific interest for these rotors is the instability in the region of half critical speed, also called gravity critical speed. General analysis of such rotors is limited to Jeffcott type beam models. This involv...

Abstract: The present paper concludes via an analytical method to reduced formulae for determining the eigenfrequencies and eigenmodes of multi-span continuous beams with spans of different lengths and bending rigidities in a very easy and efficient way. The rigorous determination of eigenfrequencies and eigenmodes allows us to focus on the derivation of the time function for the forced vibrati...

An investigation of the beam-beam interaction as a function of transverse separation of colliding proton and antiproton bunches is presented. A mathematical model describing resonant excitation of separated beams is examined. Beam-beam experiments in the Fermilab collider measure beam-beam resonant excitation ~particle losses! at different transverse beam separations in the storage ring. The ex...

The numerical results from a finite element (FE) model often differ from the experimental results of real structures. FE model updating is often required to identify and correct the uncertain parameters of FE model and is usually posed as an optimisation problem. Setting up of an objective function, selecting updating parameters and using robust optimisation algorithm are three crucial steps in...

The problem of an Euler-Bernoulli cantilever beam whose free end impacts with a point constraint is revisited from the point of view of modal analysis. It is shown that there is non-uniqueness of consistent impact laws for a given modal truncation. Moreover, taking an N-mode compliant, bilinear formulation and passing to the rigid limit leads to a sequence of impact models that does not converg...

A matrix iterative method is developed for modal sensitivify analysis of structures, which can be utilized ,a both distinct and repeated eigenvalue cases. The novel method needs only firs: order derivatives of the system motrices in the repeated e;genvalue case, and is easy to be implemented. A matrix iterative algorithm is presented based on the existence and uniqueness of the governing equati...

  In this article, vibration analysis of an Euler-Bernoulli beam resting on a Pasternak-type foundation is studied. The governing equation is solved by using a spectral finite element model (SFEM). The solution involves calculating wave and time responses of the beam. The Fast Fourier Transform function is used for temporal discretization of the governing partial differential equation into a se...

In earlier work we gave a game-based semantics for checkonly QVT-R transformations. We restricted when and where clauses to be conjunctions of relation invocations only, and like the OMG standard, we did not consider cases in which a relation might (directly or indirectly) invoke itself recursively. In this paper we show how to interpret checkonly QVT-R – or any future model transformation lang...