Determination of Dynamic Parameters of Buildings by Operational Modal Analysis

Dynamic behavior of structures depends on dynamic characteristics of structures. The dynamic characteristics are determined according to the structural properties, material properties, boundary conditions and damage cases of the structure. It is known that the dynamic characteristics of buildings vary depending on the construction stages. In this study, the dynamic characteristics of three buildings having different level of construction are determined using experimental measurements. The natural frequencies, mode shapes and modal damping ratios of these buildings are extracted from the measured data. Also, the first natural frequencies of these building are calculated using empirical relationships. The measured and calculated values of the first natural frequencies are compared for each building. It is observed from the study that the predicted dynamic behaviors of these buildings are attained from experimental measurements, and the first measured natural frequencies of these buildings are greater than the calculated frequencies.