Detecção de danos em elementos de concreto por meio de correlação de imagens digitais

Abstract

Damage structural analysis is an important research topic for several fields of engineering, capable of providing relevant information regarding structural integrity, and of guiding decisions related to intervention actions. Due to the theme’s necessity and importance, several studies have been developed to conceive techniques to assist in the quantification of technical testing procedures. The present work is inserted in this aspect. In this research, the application of an optical-numerical technique, the Digital Image Correlation (DIC), is studied to support the acquisition of information for damage analysis, in which, through a static method (the variation of deflection), it seeks to analyze the structural integrity of concrete elements through loss of bending stiffness. The idea is to compare the information obtained by the DIC, using an open source software, ITOM, with a traditional acquisition method, LVDT (Linear Displacement Transducers). To evaluate the stiffness loss, eight beams were analyzed through the bending test, providing a controlled environment for the use of this non-destructive test. Considering the results obtained, it was possible to verify the potential of CID, which was able to quantify crack openings directly in images and to represent kinematic fields through color maps, even in the development and improvement phase. The technique also shows itself useful in providing support for analysis of structures in ultimate limit state (ELU) and service (ELS), presenting displacement values with an approximation of up to 91.4% between the analysis techniques. In addition, this study draws attention to the importance of defining an experimental procedure for proper functioning of CID, since it directly impacts the results.