Orientation effects of horizontal seismic components on longitudinal reinforcement in R/C frame elements

Abstract. The present paper investigates the influence of the orientation of recorded horizontal ground motion components on the longitudinal reinforcement of R/C frame elements within the context of linear response history analysis. For this purpose, three single-story buildings are analyzed and designed for 13 recorded bi-directional ground motions applied along the horizontal structural axes. The analysis and design is performed for several orientations of the recording angle of the horizontal seismic components. For each orientation the longitudinal reinforcement at all critical cross sections is calculated using four methods of selecting the set of internal forces needed to compute the required reinforcement. The results show that the reinforcement calculated by three of the applied methods is significantly affected by the orientation of the recording angle of ground motion, while the fourth one leads to results which are independent of the orientation of the recording angle.