Seismic response of asymmetric systems with linear and non-linear viscous dampers

The seismic response of linearly elastic, single-storey, one-way asymmetric building with linear and non-linear viscous dampers is investigated. The response is obtained by numerically solving the governing equations of motion. The effects of eccentricity ratio, uncoupled lateral time period, ratio of uncoupled torsional to lateral frequency and supplemental damping eccentricity ratio are investigated on peak responses which include lateral, torsional and edge displacements and their acceleration counter parts as well as control forces. To study the effectiveness of dampers, the controlled response of asymmetric system is compared with the corresponding uncontrolled response. Further, to study the effects of torsional coupling, the controlled response of asymmetric system is compared with the corresponding symmetric system. It is shown that the non-linear viscous dampers are quite effective in reducing the responses and the damper force depends on system asymmetry and supplemental damping. Also, the effectiveness of dampers significantly depends on structural and damping eccentricity ratio and torsional to lateral frequency ratio and the effects of torsional coupling are found to be more significant for torsionally flexible and strongly coupled systems. Further, effects of torsional coupling are less for asymmetric systems with non-linear dampers as compared to linear dampers.