Structural Deformation Measurement Using MATLAB Image Processing Toolbox

Abstract

This paper describes the use of digital photogrammetry for measurement of deflections in concrete beams during the bending test. This new method to measure displacements in the experimental mechanics without applying digital sensors to the specimens is described. The optical technique uses a camera, a computer with frame grabber board and image analysis techniques within the MATLAB Image Processing Toolbox. The displacements at the surface of the test specimens are obtained by the analysis of the movements of dots painted on the specimen. The image analysis algorithm makes it possible to automatically track the motions of the dots and compute their centroid coordinates in a sequence of images. The aim of the study is to examine the surface deformations of the reinforced concrete under uniaxial loading and to compare with the results obtained from traditional instruments. 

Keywords

• bending test,deflection measurement,digital image processing

References

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