Damping Characteristic Identification of a Three-Storey Aluminium Frame Using Vibration Response Data

Monitoring large structural systems for assessing the potential degradation of structural properties by identifying the dynamic characteristics is needed for assuring safety of the system. Measurements made at a single point in the structure can be used to detect, locate and quantify damage. In this work, a method for determining the damping characteristics of a structure from the measured modal characteristics is presented. This method uses the dynamic properties obtained from the vibration response of the structure. A three-storied aluminium base frame and 8 damage-induced frames were experimentally studied by horizontal shake table. Damage was induced on the base frame by reducing the cross section of the column. The experimental observations on frequency, displacement and acceleration were used to obtain the dynamic characteristics of the structure. By comparing both theoretical and experimental results of the storey-level deflection, damping ratio of the structure is identified.