An innovative passive control technique for industrial precast frames

A feasibility study is presented on the extension to reinforced concrete (RC) precast industrial buildings of a passive control technique aiming to provide additional damping to the structure and previously proposed for RC and steel framed structures. This technique, based on the insertion of friction devices in the region of beam-to-column connections, is particularly advantageous due to the reduced dimension and low cost of the devices adopted. In the case of precast buildings, it offers the additional advantage of providing ductility to the hinged connections. In this work a general criterion for the device calibration is proposed; the modeling strategy for the device within a well-known simulation platform is presented. A prototype building is designed for a medium-to-high seismic risk and the device is fine-tuned for this particular building. The device efficiency in modifying favorably the structural behavior is analyzed by comparing the seismic response of the bare and redesigned frame to twelve accelerograms having a PGA equal to the design value. A non-critical shear increase in the zones where the device is inserted is found, largely counteracted by the reduction in extreme values for top displacement, bending moment at the column base and amount of energy dissipated in the hysteresis of materials.