Base Shear Coefficients and Displacement Amplification Factors of Tall Buildings with Tubular and Outrigger Bracing Systems on Flexible Soil

Document Type : Research Article

Authors

1 Department of Civil Engineering, Isfahan University of Technology, Esfahan, Iran

2 Senior Structural Engineer, Esfahan, Iran

Abstract

Currently, the framed-tube and outrigger-braced systems are known as two conventional load bearing systems in tall buildings. These structural systems can be used in tall buildings with high efficiency to provide the necessary lateral stiffness and strength against lateral forces due to earthquakes or strong storms. On the other hand, increasing the stiffness of these structures augments the relative importance of flexibility of the underlying soil and the resulting added displacements. This paper aims to study the seismic behavior of framed-tube and outrigger-braced tall buildings on flexible soil in comparison to a rigid base. For this purpose, a range of 10 to 50-storey steel buildings with both structural systems on flexible and rigid bases are analyzed dynamically and the maximum base shear and lateral roof displacement are calculated. Also for comparing the benefit of each system, the total weight of steel used per system in each case is calculated. Results indicated that the design spectrum of Standard 2800 overestimates the response of the studied systems. Overall, the tubular system more economically provides the necessary stiffness and strength of the building system.

Keywords

Main Subjects

References

[1] K.-S. Moon, J.J. Connor, J. E.Fernandez, Diagrid Structural Systems For Tall Buildings; Characteristics and Methodology for Preliminary design, Struct. Design Tall Spec. Buildings, 16 (2007) 205-230.
[2] F.R. Khan, N.R. Amin, Analysis and Design of Framed Tube Structures for Concrete Buildings, ACI, Pub, (1973) 39-60.
[3] R. Rahgozar, A. Ahmadi, O. Hosseini, M. Malekinejad, A simple mathematical model for static analysis of tall buildings with two outrigger-belt truss systems, International Journal of Structural Engineering and Mechanics, 40(1) (2011) 65-84.
[4] M. Malekinejad, R. Rahgozar, Free vibration analysis of tall buildings with outrigger-belt truss system, An International Journal of Earthquakes and Structures, 2(1) (2011) 89-107.
[5] M. Tajasem, Seismic performance of tubular tall structures., Islamic Azad University Yazd branch 2012.
[6] B.S. Taranath, Optimum belt truss locations for high-rise structures AISC Engineering Journal, 11(First Quarter) (1974) 18-21.
[7] B.S. Taranath, Stractural analysis and design of tall buildings in, McGraw-Hil, 1988, pp. 257-278.
[8] H. Kazemi Niakarani, F. Khoshnoudian, Seismic behavior of tall buildings and a solution for the shear lag phenomenon, in: National Congress of Civil Engineering, Mashhad University, 2011.
[9] P. Uniform Building Code, CA., in: International Conference of Building Officials, 1994.
[10] J.M.W. Brownjohn, T.-C. Pan, X.Y. Deng, Correlating dynamic characteristics from field measurements and numerical analysis of a high-rise building, Earthquake Engineering and Structural Dynamics, 29(4) (2000) 523-543.
[11] F.R. Khan, N.R. Amin, Optimal Design of Frame Tube Structures for Tall Concrete Buildings, Structural Engineering, 51(3) (1973) 85-92.
[12] A. Coull, B. Bose, Simplified Analysis of Frame – Tube Structures, J. struct. Div. , ASCE, , 101(11) (1975) 2223-2240.
[13] A. Kheiroddin, H. Jamshidi, Study of tubular resisting structural systems in tall buildings, in: National Conference on Structural Strengthening, Yazd, 2009.
[14] S.S. B., A. Cool, Analysis and Design of Tall Buildings, University of Mashhad Publications, 1997.
[15] A.H. Mohajeri, Base shear and roof displacement variation of tubular and outrigger-brace tall buildings on flexible base, University of Yazd, 2000.
[16] S.a.C.C.C.P. B. Taranath, , Group, 2012, Structural Analysis and Design of Tall Buildings, Taylor & Francis, 2012.
[17] R. Razani, M. Keivani, Effect of outrigger bracing on the behavior factor of steel structures, in: Fourth International Conference on Seismology and Earthquake Engineering, Tehran, 2004.
[18] D. Nimmy, R. Renjith, Analytical Investigation on the Performance of Tube-in-Tube Structures Subjected to Lateral Loads, International Journal of Technical Research and Applications, July-August 2016 284-288.
[19] G.W.M. HO, The Evolution of Outrigger System in Tall Buildings, International Journal of High-Rise Buildings, 5(1) (2016) 21-30.
[20] J.M.W. Brownjohn, T.C. Pan, Response of a tall building to long distance earthquakes, Earthquake Engineering and Structural Dynamics, 30 (2001) 709–729
[21] M. Jami, Calculation of the design spectrum based on the seismic records of Khorasan province using the Newmark-Hall method, International Institute of Earthquake Engineering and Seismology, 1998.
[22] Standard 2800, Seismic Design Regulations for Buildings, in: Building and Housing Research Center, 2009.
Amirkabir Journal of Civil Engineering
Volume 49, Issue 4
March 2018
Pages 723-732

Files

Share

How to cite

Statistics