Heuristic design procedure for structures with displacement-dependent damping devices
Purpose - The use of supplemental damping to dissipate energy is one of the most economical and effective ways to mitigate the effects of earthquake on structures. For practicing engineers, the ideal design procedure for buildings with supplemental damping should not be too complex to implement in practice. Building on the existing theoretical frame, the purpose of this paper is to develop simple and heuristic methods for the above design procedure. Design/methodology/approach - Passive displacement-dependent devices are considered in this paper. Based on the theoretical results for added damping and added stiffness (ADAS) devices, the paper first analyzes the generated forces and the effects of ADAS devices on structures under seismic impact. We identify design parameters and variables are identified, and present the procedure of how the values of the variables (e.g. column shear force, ductility ratio) are finalized so that the design requirements can be met is presented. A four-story six-bay steel building frame and a ten-story, one-bay steel building frame, equipped with ADAS devices, are used to demonstrate the performance of the design procedure. Findings - Empirical results show that the arrangement of damping devices based on the proposed procedure not only significantly reduces earthquake-induced energy, but also accomplishes the goal of being cost-effective by the control of ductility ratio. Originality/value - The proposed step-by-step procedure is easy for practicing engineers to apply for structures equipped with displacement-dependent dampers, although the modeling requirements may be complex. It will also allow practicing engineers to effectively design economic seismic dampers in the preliminary design phase and further explore the cost factors by comparing different building seismic performance objectives throughout design.
damping earthquakes structural design seismic loading framed structures