Plane waves and modal waves of the Timoshenko beam model are characterized in closed form by introducing robust matrix basis that behave according to the nature of frequency and wave or modal numbers. These new characterizations are given in terms of a finite number of coupling matrices and closed form generating scalar functions. Through Liouville's technique, these latter are well behaved at ...

Experimental methods used to determine the dynamic behaviour of helicopter structures can be broadly categorised as either ground testing methods or in-flight testing methods. A major limitation of ground testing is that dynamic properties determined from a grounded helicopter structure are usually significantly influenced by the boundary conditions. Therefore, it is desirable to carry out test...

the occurrence of chatter vibrations in boring operation has a great influence in improving workpiece dimensional accuracy, surface quality and production efficiency. in this paper instability analysis of machining process is presented by dynamic model of boring machine. this model, which consists of machine tool’s structure, is provided by finite element method and ansys software. the model is...

This paper presents a recursive method of modal parameters identification based on operational measurements, dedicated for non-stationary systems. Decoupling signal components procedure allowed to reduce the signal model and simplified the process of modal parameters estimation. Adaptive method of filtering simplified the process of wavelet function selection. Presented method utilize Continuou...

Elastic-plastic behavior of a beam made of functionally graded material is investigated in this work‎. ‎The beam is subjected to the constant axial and bending loads and the critical values of these loads for yield‎, ‎collapse and elastic-plastic conditions are obtained‎. ‎The variation of elastic modulus and yield strength through the height of the beam is determined with an exponential rule‎....

The aim of this paper is to investigate geometrically nonlinear static analysis of axially functionally graded cantilever beam subjected to transversal non follower load. The considered problem is solved by finite element method with total Lagrangian kinematic approach. The material properties of the beam vary along the longitudinal direction according to the power law function. The finite elem...

In this paper, model reference neural network structure is used as a controller for vibration suppression of the Euler–Bernoulli beam under the excitation of moving mass travelling along a vibrating path. The non-dimensional equation of motion the beam acted upon by a moving mass is achieved.  A Dirac-delta function is used to describe the position of the moving mass along the beam and its iner...

This paper describes the detection and identification of cracking severity in a reinforced concrete beam using modal data. Experimental modal test was performed on the beam before and after application of load of increasing intensity to induce a single crack at a fixed location. Modal parameters extracted were categorised into hvo groups, namely local response parameter (mode shape data) and gl...

The present study investigates buckling characteristics of both nonlinear symmetric power and sigmoid functionally graded (FG) beams. The volume fractions of metal and ceramic are assumed to be distributed through a beam thickness by the sigmoid-law distribution (S-FGM), and the symmetric power function (SP-FGM). These functions have smooth variation of properties across the boundary rather tha...

This paper presents a technique to predict the severity and the location of the damage in beam-like composite laminates by using modal parameters as input for an artificial neural network. A laminated cantilever beam is modelled using ANSYS 5.6© finite element software. Normal mode dynamic analyses have been performed for the first three natural modes of intact and damaged beams to find the mod...