A new damage detection method using curvature mode shapes with considering the noise of the data transmission and minor damages

Abstract

With the increasing global population in recent decades and the increasing number of construction projects in the world, researchers and scientists from various sciences are thinking about restoration of civil engineering structures, which has reached to useful life of many of these structures. The failure of part of these structures leads to the destruction of the entire structure, which results in the wasting of large amounts of capital from owners and owners of these structures. Destruction and rebuilding of such structures are not at all cost-effective. Therefore, the science of health monitoring of structures in order to solve these problems has attracted researchers in recent years. So far, various methods, including X-rays and ... have been used to find the damaged member, but these methods can only be used on members of the structure that is available. And they are not comprehensive for the whole structure. For this purpose, vibration-based methods were introduced. Among the vibration-based methods, modal field methods have been of major interest to the researchers for their simplicity in performance. One of these methods is the mode shape curvature method, whose intrinsic ability to detect and locate damage is obvious to everyone. In this study, taking into account the noise generated by the mode shape data acquisition, more careful attention is needed in the field of damage detection. For this reason, the damage index was used as an indicator of the damage. The results indicate high accuracy of the method in identifying low-intensity damage and high noise level in higher modes.

Keywords

• structure health monitoring
• locating the damage
• mode shape curvature
• damage index
• noise