The Optimal Number of Outriggers in a Structure Under Different Lateral Loadings

  • Sajjad BaygiEmail author
  • Amin Khazaee
Original Contribution


In this paper, the optimum number of outriggers in a structure for minimizing top story displacement under lateral loads is investigated. To do so, the base moment and top story displacement are formulated. Then, a MATLAB code is employed to find the optimum positions of the outriggers. Different kinds of lateral loads including concentrated, uniform, triangular are taken into account. Moreover, the effects of the variation of structural elements such as column, outriggers and core on the optimal number of outriggers are examined. The results showed that the best number of outriggers depends on parameters such as axial rigidity of columns, distance of outer columns, flexural rigidity of outriggers and height of structure; by changing these parameters, the optimum number of outriggers will be changed.


Outrigger High-rise building Optimum location Moment diagrams Flexural rigidity Optimum number 



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Copyright information

© The Institution of Engineers (India) 2019

Authors and Affiliations

  1. 1.Department of Civil EngineeringFerdowsi University of MashhadMashhadIran
  2. 2.Department of Civil EngineeringEsfarayen Higher Education of Engineering and TechnologyEsfarayenIran

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