Seismic performance of steel frame structures equipped with novel displacement-amplified friction dampers

Conventional friction dampers (FDs) have a limited energy dissipation capacity due to the small inter-storey displacement of building structures. To address this, a novel friction damper with a displacement amplification mechanism based on the lever principle is proposed to provide high energy dissipation capacity with reduced displacement. Firstly, the components and working principle of an amplified friction damper (AFD) are described, the theoretical equation of its restoring force is derived, and its rationality is verified using MATLAB and the secondary development function of ABAQUS. The high-rise steel frame structure model is established using ABAQUS, and the rationality of the model is verified by modal analysis of the structural model using YJK (finite element modeling software). To compare the dynamic response of uncontrolled original structures and damped structures, dynamic time analysis is carried out for structures without control, with additional ordinary friction dampers (FD), and with additional lever amplified friction dampers (AFD-2 and AFD-3, i.e., AFD with an amplification of 2 and 3, respectively). Analysis results indicate significant reductions in inter-storey displacement angles and base shear under rare earthquakes: 24.0 %, 39.0 %, and 54.0 % for FD, AFD-2, and AFD-3 models, respectively. Subsequently, a vulnerability analysis using the incremental dynamic analysis (IDA) method evaluates the impact of additional AFD on structure seismic performance in terms of failure probability. Compared to FDs, AFD-2 and AFD-3 models demonstrate reductions in failure probabilities of approximately 16.6 % and 29.7 %, respectively, across various ultimate damage states and ground shaking magnitudes. Additionally, their collapse resistance reserve CMR values increase by 21.3 % and 38.2 %, respectively. These findings underscore the superior seismic stability of steel frame structures with displacement-amplified friction dampers, offering valuable insights for seismic-resistant design strategies in earthquake-prone areas.