A study of ADAS element parameters and their influence on earthquake response of building structures.

Abstract

The objective of this research was to study the ADAS (added damping and stiffness) element parameters and their influence on earthquake response of building structures. The results of this study provide a better understanding of the ADAS parameters and their effects on seismic response and can be used as a reference for the design of building structures with ADAS elements. The selected parameters included the device yield force, the device yield displacement, the device strain-hardening ratios, the ratio of the bracing member stiffness to the device initial elastic stiffness, the ratio of ADAS element stiffness to the structural story stiffness without ADAS elements in place, and the distribution of ADAS elements. The selected response parameters include the floor displacement, the story displacement, the story shear force, the device ductility ratio, the structural member ductility ratio, and the seismic input energy and the energies dissipated by structures. The 1940 El Centro (NS) earthquake, the 1985 Mexico City (SCT Station, EW) earthquake, and the 1978 Miyagi-Ken-Oki earthquake were used to generate the inelastic structural responses. Different earthquake record scale factors were used to account for different earthquake intensities. The response of three ten-story moment frames with different ADAS elements were calculated by using the modified DRAIN-2D program. The influence of ADAS parameters on these three frames were analyzed. A design example was given to illustrate the procedure and criteria for the design of a building structure with ADAS elements. The analytical results of the designed structure showed that properly designed ADAS elements can effectively control the inelastic response of building structures. Design of ADAS elements should consider device energy dissipation capacity within the maximum design ductility ratio, and the earthquake characteristics, intensity and energy demands.