Damping from vibration records of tall buildings

Gümüştepe, Anıl Can
With the release of the new Turkish Building Earthquake Code, real-time structural response monitoring of tall buildings became mandatory. As part of two research projects undertaken at Middle East Technical University and Bogazici University to develop the structural health monitoring guidelines, two tall buildings in Izmir and Istanbul were instrumented, respectively. This thesis focuses on the damping estimations of the tallest building in Izmir from its ambient vibration records. Structural response of the building is currently monitored in real time by a dense network of 27 channels of accelerometers. Using the random decrement method, the modal damping ratios of the building were identified for the first four modes in the East-West and North-South translational directions and in the torsional direction. The mean damping ratios were 0.6–1.0% with coefficients of variation in the order of 0.10–0.40 for the first two modes. The identified modal damping ratios were compared with the values from code and other formulations in literature as well as other instrumented tall buildings. The time history analyses were performed to reproduce the recorded strong motion responses of the building during the 2019 Mw 5.0 Ayvacik, Canakkale and Mw 5.8 Marmara Sea, Istanbul earthquakes using both identified and code-specified damping ratios in the existing finite element model of the building to evaluate the impact of damping on structural responses.
Citation Formats
A. C. Gümüştepe, “Damping from vibration records of tall buildings,” M.S. - Master of Science, Middle East Technical University, 2023.