Behaviour of RC Buildings with Single and Double Outriggers under Seismic Response

Today, tall structures are inescapable in urban communities. Along these lines, the structure requires a production system which can effectively participate in resisting the applied wind and earthquake loads. Among the available lateral load resisting systems, outrigger, as rigid horizontal elements connect shear walls to exterior columns is the most commonly used to enhance tall structures performance under lateral forces. A series of dynamic response spectrum (RS) analyses devoted to assess the seismic response behavior of R.C tall buildings with central core wall having outrigger system. Several models with and without outrigger systems were considered in the analysis in order to investigate the ideal position and the number of outriggers. The developed building models have either one or two outriggers. Structural software package ETABS was used to develop the considered herein different configurations of the building models as well as performing the dynamic analysis. The performance of the considered different configurations was investigated in terms of displacement and inter-storey drift peak profiles. Sensitivity to the position of outrigger on the induced wall bending moment was also explored comparing the responses of the different configurations. The results of the performed study can provide structural designers with the optimum location of a single or either double outrigger in order to minimize the induced seismic response during the initial stage of the outrigger system design process. The optimum locations of outriggers are quarter height of the building in case of using single outrigger and at quarter and three quarters of the building in case of using double outrigger in order to minimize the induced moment values on the core and column