Towards a simplified Direct DBD procedure for the seismic design of moment resisting frames with viscous dampers

In this paper a new methodology for the Direct displacement-based seismic design (DBD) of moment resisting frame (MRF) structures fitted with viscous dampers is proposed. The approach builds on previous recommendations for Direct DBD and gives the designer a simplified non-iterative means of controlling the system damping of the structures by choosing proportions of force resisted by the dampers relative to the main structure. Non-linear time-history analyses of a 9-storey case study structure fitted with linear viscous dampers illustrate that the new procedure may prove to be very useful for design. Future research should aim to better verify the approach and extend it to the use of frames possessing non-linear viscous dampers.