Crack detection in beam

In the present study, a novel indicator extracted from FRFs of beam structures is developed for crack identification. The damage indicator originated from the well-known mode assurance criterion (MAC) and therefore it is termed spectral assurance criterion (SAC).

14p vijeff 30-11-2023 7 3   Download

An explicit expression of natural frequencies through crack parameters is derived for multiple cracked beams with simply supported boundaries using the Rayleigh quotient. The obtained expression provides not only a simple tool for calculating natural frequencies of multiple cracked beams, but also allows employing the so-called crack scanning method for detecting multiple cracks in simply supported beams from measured natural frequencies.

13p viwolverine 11-07-2023 6 3   Download

The problem of using the modal curvature for crack detection is discussed in this paper based on an exact expression of mode shape and its curvature. Using the obtained herein exact expression for the mode shape and its curvature, it is demonstrated that the mode shape curvature is really more sensitive to crack than mode shape itself. Nevertheless, crack-induced change in the approximate curvature calculated from the exact mode shape by the central finite difference technique (Laplacian) is much greater in comparison with both the mode shape and curvature.

10p nguaconbaynhay11 07-04-2021 19 2   Download

This paper presents the derivation of the exact receptance function of continuous cracked beams and its application for crack detection. The receptance curvature is defined as the second derivative of the receptance. The influence of the crack on the receptance and receptance curvature is investigated. It is concluded that when there are cracks the receptance curvature has sharp changes at the crack positions. This can be applied for the crack detection purpose. In this paper, the numerical simulations are provided.

13p nguaconbaynhay11 07-04-2021 8 2   Download

The aims of this study are to develop and apply the method of using frequency response functions to diagnose cracks in elastic bar and beams structure. The contents of the study includes: building models of cracked elastic bar and 3 beams structure; studying the changes of oscillation parameters, mainly frequency response functions due to cracks.

27p larachdumlanat129 20-01-2021 19 5   Download

In this paper, efforts are made to develop suitable methods that can serve as the basis to detect crack location and to crack size from measured axial vibration data. This method is used to address the inverse problem of assessing the crack location and crack size in various beam structure.

8p tohitohi 19-05-2020 12 0   Download

The aim of this thesis is to study crack-induced change in natural frequencies and to develop a procedure for detecting cracks in stepped beams by measurement of natural frequencies.

27p xacxuoc4321 11-07-2019 28 3   Download

Model of crack was studied by many authors. Adams R. D. and Cawley P. in 1978 have proposed an axial spring model [1] to investigate the problem of location of crack in a bar using natural frequencies and mode shape.

10p chikychiky 26-10-2018 30 0   Download

This is based an explicit expression of the natural frequencies in term of crack parameter derived in the form similar to the so-called Rayleigh quotient for vibrating beam. The obtained simple relationship between natural frequencies and crack parameters enables not only accurate calculating the natural frequencies but also to develop an efficient procedure for detecting multiple cracks from given natural frequencies.

16p thienthanquydu 19-10-2018 33 1   Download

In this paper an idea for crack detection of a multi-cracked beam-like structure by analyzing the vibration measured directly from the vehicle is presented. The crack model is adopted from fracture mechanics. The dynamic response of the bridgevehicle system is measured directly from the moving vehicle. When the vehicle moves along the structure, the dynamic response of the vehicle is distorted by the cracks at their locations.

13p thienthanquydu 17-10-2018 28 0   Download

Rayleigh’s quotient for Euler-Bernoulli multiple cracked beam with different boundary conditions has been derived from the governed equation of free vibration. An appropriate choosing of approximate shape function in terms of mode shape of uncracked beam and specific functions satisfying conditions at cracks and boundaries leads to an explicit expression of natural frequencies through crack parameters that can simplify not only the analysis of natural frequencies of cracked beam but also the crack detection problem.

12p thienthanquydu 17-10-2018 29 0   Download