Reduction of seismic forces on existing buildings with newly constructed additional stories including friction layer and dampers

This paper presents a new approach to improve seismic readiness of story-increased buildings by utilizing passive structure control techniques. This approach uses passive structural control techniques such as sliding-friction layer and dampers. The sliding-friction layer is sandwiched between the bottom surface of the increased structure and the rooftop of the original building. The energy dissipation dampers are installed between the supporting outer frame for the increased-structure and each floor of the original buildings. To assist dynamic analysis and control design, a simplified structural model of the building system is derived. To increase computational accuracy and to reduce computation time, a novel Coulomb friction representation is incorporated into the non-linear dynamic analysis. The proposed method is applied to a story-increased building and numerical results demonstrate the effectiveness of the proposed method. (C) 2003 Elsevier Ltd. All rights reserved.