Proposal of the Location and Shape of the Outrigger Arm and Belt Truss in the High-Rise Buildings with the Central Core

Document Type : Research


1 Professor, Faculty of Civil Engineering, Babol Noshirvani University of Technology, Iran.

2 Assistant Professor, Faculty of Civil Engineering, Ayandegan Institute of Higher Education, Tonekabon, Iran.

3 M.Sc. Student, Faculty of Civil Engineering, Tabari University of Babol, Iran.


The outrigger arm system and belt truss with braced core in the center of the structure surrounded by belts truss, is an efficient and reliable system for high-rise buildings against severe lateral forces such as earthquake and wind. The purpose of this research is investigating the outrigger arm system and belt truss with the braced core under lateral loads. Another purpose of this research is to reduce the drift and displacement of the roof against these loads with deformation and finding the optimal location for the outrigger arm by/through various methods. Analysis of nonlinear time history and spectral analysis of the site with a high relative risk for the three models of 30, 45, and 60 floors have shown that the optimum location of the outrigger arm and belt truss with the proposed method in this research has been better more noteworthy than the previous methods and caused decreasing as it has induced/brought about a decrease in absolute roof displacement and maximum relative displacement of floors. The suggested deformation for outrigger arm in addition to reducing the stress concentration in the floors where outrigger arm are is installed, has caused a significant reduction in the absolute change in the roof of the building and the maximum relative displacement of the floors.


1. Smith, B. S., Coull, A., & Stafford-Smith, B. S. (1991). Tall building structures: analysis and design (Vol. 5). New York: Wiley.
2. Meftah, S. A., Tounsi, A., & El Abbas, A. B. (2007). A simplified approach for seismic calculation of a tall building braced by shear walls and thin-walled open section structures. Engineering Structures, 29(10), 2576-2585. [DOI:10.1016/j.engstruct.2006.12.014]
3. Ji, J., Elnashai, A. S., & Kuchma, D. A. (2007). An analytical framework for seismic fragility analysis of RC high-rise buildings. Engineering structures, 29(12), 3197-3209. [DOI:10.1016/j.engstruct.2007.08.026]
4. Khoshnoudian, F., & Kashani, M. M. B. (2012). Assessment of modified consecutive modal pushover analysis for estimating the seismic demands of tall buildings with dual system considering steel concentrically braced frames. Journal of Constructional Steel Research, 72, 155-167. [DOI:10.1016/j.jcsr.2011.12.002]
5. Kheyroddin, A., & Aramesh, S. (2015). Lateral Resisting System inTall Buildings.
6. Montuori, G. M., Mele, E., Brandonisio, G., & De Luca, A. (2014). Design criteria for diagrid tall buildings: Stiffness versus strength. The Structural Design of Tall and Special Buildings, 23(17), 1294-1314. [DOI:10.1002/tal.1144]
7. Montuori, G. M., Mele, E., Brandonisio, G., & De Luca, A. (2014). Geometrical patterns for diagrid buildings: Exploring alternative design strategies from the structural point of view. Engineering Structures, 71, 112-127. [DOI:10.1016/j.engstruct.2014.04.017]
8. Montuori, G. M., Mele, E., Brandonisio, G., & De Luca, A. (2014). Secondary bracing systems for diagrid structures in tall buildings. Engineering Structures, 75, 477-488. [DOI:10.1016/j.engstruct.2014.06.011]
9. Takewaki, I., Murakami, S., Fujita, K., Yoshitomi, S., & Tsuji, M. (2011). The 2011 off the Pacific coast of Tohoku earthquake and response of high-rise buildings under long-period ground motions. Soil Dynamics and Earthquake Engineering, 31(11), 1511-1528. [DOI:10.1016/j.soildyn.2011.06.001]
10. Trabelsi, A., Kammoun, Z., & Beddey, A. (2017). Seismic retrofitting of a tower with shear wall in UHPC based dune sand. Earthquakes and Structures, 12(6), 591-601.
11. Coull, A., & Bose, B. (1975). Simplified analysis of frame-tube structures. Journal of the Structural Division, 101(11), 2223-2240. [DOI:10.1061/JSDEAG.0004200]
12. Coull, A., & Ahmed, A. K. (1978). Deflections of framed-tube structures. Journal of the Structural Division, 104(5), 857-862. [DOI:10.1061/JSDEAG.0004919]
13. Connor, J. J., & Pouangare, C. C. (1991). Simple model for design of framed-tube structures. Journal of structural engineering, 117(12), 3623-3644. [DOI:10.1061/(ASCE)0733-9445(1991)117:12(3623)]
14. Moghadam, M. A., Meshkat-Dini, A., & Moghadam, A. S. (2015, May). Seismic performance of steel tall buildings with outrigger system in near fault zones. In Proceedings of the 7th International Conference on Seismology & Earthquake Engineering.
15. Brunesi, E., Nascimbene, R., & Casagrande, L. (2016). Seismic analysis of high-rise mega-braced frame-core buildings. Engineering Structures, 115, 1-17. [DOI:10.1016/j.engstruct.2016.02.019]
16. Kim, J., & Park, J. (2012). Progressive collapse resisting capacity of building structures with outrigger trusses. The Structural Design of Tall and Special Buildings, 21(8), 566-577. [DOI:10.1002/tal.628]
17. Chen, Y., & Zhang, Z. (2018). Analysis of outrigger numbers and locations in outrigger braced structures using a multiobjective genetic algorithm. The Structural Design of Tall and Special Buildings, 27(1), e1408. [DOI:10.1002/tal.1408]
18. Hoenderkamp, J. C. D. (2008). Second outrigger at optimum location on high‐rise shear wall. The structural design of tall and special buildings, 17(3), 619-634. [DOI:10.1002/tal.369]
19. Kim, H. S., & Kang, J. W. (2017). Smart outrigger damper system for response reduction of tall buildings subjected to wind and seismic excitations. International journal of steel structures, 17(4), 1263-1272. [DOI:10.1007/s13296-017-1201-1]
20. Kamgar, R., & Rahgozar, R. (2017). Determination of optimum location for flexible outrigger systems in tall buildings with constant cross section consisting of framed tube, shear core, belt truss and outrigger system using energy method. International Journal of Steel Structures, 17(1), 1-8. [DOI:10.1007/s13296-014-0172-8]
21. Standard 2800 (2019), Iranian code of practice for seismic resistant design of buildings standard No. 2800, Version 4
22. Kim, S., & D'Amore, E. (1999). Push-over analysis procedure in earthquake engineering. Earthquake Spectra, 15(3), 417-434. [DOI:10.1193/1.1586051]
23. Sap 2000 (2015). Structural analysis program (SAP). Computers and Structures, Inc, Version 18.01, USA.
24. Faghihmaleki, H., & Abdollahzadeh, G. (2019). Using risk-based robustness index for seismic improvement of structures. KSCE Journal of Civil Engineering, 23(3), 1207-1218. [DOI:10.1007/s12205-019-0350-5]
25. Taranath, B. S. (1975). Optimum belt truss location for high-rise structures. Structural Engineer 53(8), 18-21.
26. Jahanshahi, M. R., & Rahgozar, R. (2013). Optimum location of outrigger-belt truss in tall buildings based on maximization of the belt truss strain energy. [DOI:10.5829/idosi.ije.2013.26.07a.03]