Desenvolvimento de sistema interferométricos para análise de deslocamentos

Abstract

In order to find an ideal experiment to be replicated in Optical Labs in Universities, four different settings of Non Destructive Interferometric Optical Essay were tested in this in this research. These settings were based on Digital Speckle Pattern Interferometry (DSPI) method, which uses a coherent light beam produced by a HeNe laser. The setting have undergone several changes on the mounting shapes, loading types (angular and by compression) and specimens used (acrylic, a piece of circuit board and concrete). The fourth setting was identified as the most appropriate, because of its cost and simplicity to be reproduced in comparison to the other owes and with commercialized equipment. This setting has made possible to better check the optical interference effects, both in the observation of the speckle phenomenon and in the fringes which aidicute discontinuity formation related to the external loadings effect. Besides that, supporting tests were realized and the efficiency of the selected setting was confirmed. The supporting tests consisted of inserting a discontinuity (circular hole) of 3,4mm in diameter and desw out depths (0 mm, 2,5 mm, 10 mm, 13 mm e 15,5 mm) in a sample of concrete (24 mm x 30 mm x 51 mm). The results proved that there is a correlation between the increase of discontinuity/hole and the results of the Non Destructive Essay (DSPI).