Best Location of Conventional Outrigger in Tall Buildings with Discontinuity in Moment of Inertia of Shear Core using Energy Method with Closed-Form Solution

Document Type : Regular Paper

Authors

1 Department of Civil Engineering, Faculty of Engineering, Shahid Bahonar ‎University of Kerman, Kerman, Iran

2 Faculty of Engineering, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran

10.22075/jrce.2025.2337

Abstract

This study presents a graphical solution for determining the ‎initial positioning of Conventional Outrigger (CO) system in ‎the shear core with discontinuity in moment of inertia, using ‎the energy method in tall building. In this model a cantilevered ‎beam presents The framed-tube system, while the CO system ‎is modeled by rotational springs located at their respective ‎positions. By applying the energy method, best locations of the ‎CO are identified along the building height to maximize energy ‎absorption and dissipation. For validation, the model is ‎compared with the case of a uniform shear core, and the ‎results are shown to be consistent with previous studies.‎‏ ‏Quantitative results indicate that when the shear core has no ‎discontinuity, the best positions of the CO are approximately ‎‎0.44L, 0.49L, 0.32L, and 0.52L of the building height (L) for ‎uniform, triangular, inverted triangular, and parabolic load ‎distributions, respectively. Furthermore, with increasing values ‎of the parameter γ, which corresponds to greater slenderness in ‎the second segment of the shear core, the best positions shift ‎upward along the building height. In some cases, the best ‎location falls within the first segment of the shear core, similar ‎to the case of a uniform shear core.‎‏ ‏The proposed closed-form ‎solution and the developed utility graphs offer a practical and ‎efficient tool for identifying the initial positioning of CO ‎system during the preliminary design of tall buildings.‎

Graphical Abstract

Best Location of Conventional Outrigger in Tall Buildings with Discontinuity in Moment of Inertia of Shear Core using Energy Method with Closed-Form Solution

Highlights

 

  • Proposing a graphical method for initial positioning of belt truss and outrigger in tall buildings with shear core discontinuity
  • Modeling the structural system using an equivalent cantilever beam and rotational springs for belt truss and outrigger representation
  • Applying the energy method to determine optimal locations that maximize energy absorption and dissipation
  • Providing practical graphs with dimensionless variables to analyze structures under uniform, triangular, inverted triangular, and parabolic load distributions

Keywords

Main Subjects

References

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History

  • Receive Date: 04 June 2025
  • Revise Date: 12 October 2025
  • Accept Date: 21 November 2025

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