Avaliação de danos em estruturas reticuladas por meio das propriedades dinâmicas

Abstract

The structures suffer many kinds of deterioration not only due to natural phenomena but also due to the action of loads of varied magnitude that when combined may cause the appearence of damages. These damages can affect the load capacity and therefore the security and working life of the buildings making necessary the researching of survey techniques which allows to identify them in an early and affordably way. The damage can be characterized by a local loss of stiffness which is responsible for causing alterations on the dynamic parameters such as natural frequencies and modes shapes. In this work two methods of damage localization were applied, the Error Residual Method (Genovese, 2000; Brasiliano, 2001; Araújo, 2013) and the APC (Approximate Paramater Change) and DSM (Damage Signature Matching) (Lam et al, 1998) techniques which are based on the comparison between the modes shapes of an intact and a damaged structure. Through a numerical analysis it was possible to make a comparison between the methods. It was also made an experimental analysis of a steel free-free beam in order to validate the numerical results