Seismic behavior of buildings with tuned mass friction dampers optimized with a novel PSO-GWO hybrid algorithm

Tuned mass friction dampers (TMFDs) are very effective at controlling the response of structures. However, the TMFDs’ parameters need to be optimized during design, which is complex if multi-degree of freedom systems (MDOF) and real ground motion records are adopted. This article examines numerically the effectiveness of TMFDs and tuned mass dampers (TMDs) at reducing the response of MDOF buildings subjected to seismic excitations. The design parameters of TMFDs and TMDs (mass, damping, frequency and friction coefficient) are first optimized by adopting a novel and efficient “hybrid” algorithm that combines a particle swarm optimization (PSO) and a grey wolf optimization (GWO). Next, four moment resisting frame buildings (3, 6, 9 and 12-stories) with a TMFD or a TMD device at the top floor are considered to derive the governing differential equations of motion. The displacement demand of the top floor is selected as a target of the objective function to be minimized. After the optimization, the four frame buildings with a TMFD/TMD device and counterpart non-controlled frames are subjected to 100 far-field and near-field (with/without pulse) earthquakes. The results show that, for equal masses, the TMFD control device can provide control performance comparable to the TMD device. For the 3,6 and 9-story buildings, the optimized TMD device reduces the displacement demand by an additional 10 % over counterpart buildings with an optimized TMFD. Conversely, for the 12-story frame, TMFD reduces the displacement demand by an additional 10 % over the TMD device. This suggests that TMFD devices are more effective in high-rise buildings. The stroke demand in the TMFD is generally superior to that provided by the TMD with respect to the displacement demand of a non-controlled building. This article contributes towards the development of more effective hybrid optimization design tools for passive control systems, which in turn is expected to promote their wider adoption in the design of controlled buildings.