Monitoramento de estruturas metálicas submetidas a variação do torque de aperto em elementos de fixação

Abstract

The integrity of a structure is influenced by a series of factors that play crucial roles in ensuring reliability and safety. Among these factors, fasteners assume particular importance in structural systems. The proper condition of these elements is fundamental for their effective application. A common example is the use of screws with specified torques for each type of application; thus, if any screw has a torque different from the specified one, it can compromise the integrity of the entire structure. Therefore, monitoring these factors is crucial to predict damage and maintenance in structural components, aiming to increase the longevity and safety of systems in general. This monitoring is done through sensors implemented to measure vibrations and identify changes in vibratory parameters throughout the structure's life span. In this study, the effects of torque variation on fastening elements such as screws in a 2-degree-of-freedom system were analyzed by monitoring the structure's vibration signals with the aid of piezoelectric sensors. At the end of the study, it was possible to identify variations in vibration parameters caused by the loosening of the fastening elements of the structure through sensory analysis. Tests with different torque configurations showed that the method was effective in identifying torque variations, especially when the screws were fully loosened. This enables the detection of possible loosening of screws in metallic structures, thus contributing to the technique of monitoring structural integrity.