Experimental Validation of Structural Damage Identification Using Vibration Transmissibility

Architectural structures suffer from the impact of design loads and various kinds of external factors on their complex service conditions, which may lead to the accumulation of structural damage. This damage may give rise to the changes in structural dimension and material property, decrease structural security and degree of reliability, as well as bring potential safety hazard to building structures. Usually, the traditional damage identification method has great limitation in practical application because it requires accurate load information which is sometimes too complicated to be precisely measured. In order to solve this problem, the vibration transmissibility method is used. The vibration transmissibility is adopted as the damage index because it can not only reflect the characteristics of the structure itself, but also does not require external load information, which is of great importance in practical application. This article discusses the use of vibration transmissibility based method for detecting, locating and qualifying structural damage. For studying the feasibility of the damage identification method based on vibration transmissibility, various numerical simulations of an 8 degree of freedom structure and experiments on a cantilever beam were conducted. The main focus was to study the repeatability, sensitivity to damage and sensitivity to the damage location of this method􀀀In the experimental verification, the external load is simulated by hammer, the different extend of damage is simulated by varying degrees of loosened bolts and varying notch length. The results of the simulations and the experiments showed that the vibration transmissibility method was a promising method because it was independent of the external load, strongly sensitive to damage, and can identify the damage locations. doi: 10.12783/SHM2015/44