Monitoring of a Tall Building Equipped with an Efficient Multiple-Tuned Sloshing Damper System

An efficient multiple tuned sloshing damper (MTSD) system is installed in a tall building in Toronto, Canada. The building is monitored before and after water is added to the tanks to measure wind-induced building motion, and evaluate the performance of the MTSD. To the authors' knowledge, this is the first time an MTSD system has been installed in a tall building, and one of the few times the as-built performance of a tall building supplementary damping system has been evaluated and reported in the literature. Monitoring of the building motion before commissioning the MTSD indicated that the structural frequencies were very close to those originally predicted by the structural engineer's finite element model. Only 0.8% inherent structural damping was measured for the first mode when the peak building acceleration was 7 milli-g. The measured and wind tunnel predicted wind-induced building accelerations are in good agreement. After commissioning the MTSD system, the measured building accelerations and MTSD wave heights are found to be well-aligned with predictions. Several techniques are used to evaluate the performance of the MTSD system using the measured data. Each technique confirms that the MTSD system reduced building accelerations by approximately 50%. Full-scale structural monitoring has therefore shown that MTSDs can significantly reduce the motion of tall buildings.