Estimation of seismic demand in tall buildings using mode-acceleration method

Abstract

The current study presented a method to estimate seismic response of inter-story drift in tall buildings. Inter-story drift is obtained using combined mode-acceleration equations via modeling tall buildings through flexural and shear cantilever beams’ equations, and estimating dynamic components of tall buildings. In the provided equation to calculate seismic response of inter-story drift, it is necessary to know details of the building, which makes it easy and expedites the analysis. Inter-story drift of 10-, 15-, and 50-story buildings for three earthquake accelerograms was estimated using the provided equation, and via finite element software OPENSEES, the equation was verified. Results comparison showed that the equation provided a good approximation, which can be used instead of modeling, to calculate inter-story drift. In addition, the comparison between the calculated inter-story drift with those of the approximate method and finite element method showed that the mode-acceleration method was close to the accurate solution even using few modes.