Structural Control Using a Semiactive Friction Damper

All civil structures are prone to vibrations caused by external sources such as earthquakes, wind, mechanical loads and anthropogenic loads. However, structural control systems have proven to be effective in reducing excessive vibrations. This article describes a Semiactive-Variable-Friction-Damper that was designed for reducing the dynamic response of structures subject to seismic excitation. The structural control device, which consists of a hydraulic brake activated with a servomotor, was identified and characterized in order to design a decentralized control strategy. A small-scale benchmark structure was built and the structure with control system was tested on a shaking-table. Results of the structural response with and without the control system are compared, with the friction device reducing story drift by up to 90 %.