Influence of bracing elements on the seismic response of multistorey frames

Abstract

The aim of this study is to deal with the influence of energy dissipation devices (braces) on the seismic response of multistorey frames. A base frame and five retrofitted frames are designed. Behavior of the original and retrofitted frames was evaluated by conducting two-dimensional, inelastic and dynamic response analyses using the nonlinear computer program DRAIN-2DX. The sections of the conventional frame are designed such that the frame is safe under static loading, but it fails when subjected to dynamic loading. The section types and lengths of all of the braces are exactly the same. This is very advantageous for the purpose of monitoring the response of geometrically differently designed bracing systems. Results of the analysis for avery frame are compared. For comparison storey displacements, storey shears, mean maximum bending moments of the columns are considered. In addition to these a vertical analyse is made for Frame 1 to see the effectiveness of the braces of different stories. A time history analysis is applied for all of the frames. The longitudinal accelogram (East-West) of Düzce earthquake is used in the analysis.