Advanced Steel Construction

Vol. 14, No. 4, pp. 710-731(2018)





G.S. Tong* and X.G. Li

College of Civil Engineering and Architecture, 

Zhejiang University, Hangzhou,Zhejiang Province, China

*(Corresponding author: E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it. )

Received:19 April 2018; Revised: 23 July 2018; Accepted: 25 July 2018




View Article   Export Citation: Plain Text | RIS | Endnote


Ultimate yield surfaces of concrete-filled L-shaped multi-celled steel tube column (L-CFT) under biaxial bending and axial force are studied in this paper. The characteristics of the axial force-bending moment interaction curves under uniaxial bending is first revealed, while the rotational symmetry of the overall interaction curve is verified mathematically. Based on the relative positions of the elastic centroid axis and the plastic neutral axis under pure bending, six cases are identified whose interaction curves show slightly different features. The interaction curves between axial force and bending moments are grouped into two categories. Finally, the interaction surfaces of L-CFT under biaxial bending and axial force are analyzed. The characteristics of these curves are discussed and verified mathematically, and further the approximate formulas for design purpose are provided. Based on the comparative study of a large number of examples, the proposed formulas show good accuracy and are on the conservative side.



Concrete-filled steel tube, multi-celled, strength, biaxial bending, interactive relation


[1] JGJ149-2006, “Technical Specification for Concrete Structures with Specially Shaped Columns”. The Ministry of Housing and Urban-Rural Development of China: Beijing, 2006.

[2] Hsu, C.T.T., “T-shaped Reinforced Concrete Members under Biaxial Bending and Axial Compression”, Aci Structural Journal, 1989, Vol. 86, No. 4, pp. 460-468.

[3] Hsu, C.T.T., “Biaxially Loaded L-shaped Reinforced Concrete Columns”, Journal of Structural Engineering, 1985, Vol. 111, No. 12, pp. 2576-2595.

[4] Sun, J.H., “Lateral Stiffness and Analysis of Frames Built of Special Shaped Columns”, Zhejiang University: Hangzhou, 2003.

[5] Zhao, Y.H., “Study on Bearing Capacity for SRC Special Shaped Columns”, Xi’an University of Architecture and Technology: Xi’an, 2007.

[6] Chen, W.F. and Atsuta, T., “Theory of Beam-columns”, McGraw-Hill: New York, 1976.

[7] Hajjar, J.F. and Gourley, B.C., “Representation of Cconcrete-filled Steel Tube Cross-section Strength”, Journal of Structural Engineering, 1996, Vol. 122, No. 11, pp. 1327-1336.

[8] CECS159-2004, “Technical Specification for Structures with Concrete Filled Rectangular Steel Tube Members”. The Ministry of Housing and Urban-Rural Development of China: Beijing, 2004.

[9] Chadwell, C.B. and Imbsen, R.A., “XTRACT: A Tool for Axial Force-ultimate Curvature Interactions”, Structures Congress, ASCE, 2004.

[10] Shen, Z.Y., Lei, M., Li, Y.Q. and Luo, J.H., “Experimental Study on Seismic Behavior of Concrete-filled L-shaped Steel Tube Columns”, Advances in Structural Engineering, 2013, Vol. 16, No. 7, pp. 1235-1248.

[11] Zuo, Z.L., Cai, J., Yang, C. and Chen, Q.J., “Eccentric Load Behavior of L-shaped CFT Stub Columns with Binding Bars”, Journal of Constructional Steel Research, 2012, Vol. 72, No. 5, pp. 105-118.

[12] Zhang, J.C., Shen, Z.Y., Lin, Z.Y., and Luo, J.H., “Experimental Research on Seismic Behavior of Concrete-filled L-section Steel Tubular Frames”, Journal of Building Structures, 2010, Vol. 31, No. 8, pp. 1-7.

[13] Wang, D. and Lv, X.L., “Experimental Study on Seismic Behavior of Concrete-filled Steel T-section and L-section Columns”, Journal of Building Structures, 2005, Vol. 26, No. 4, pp. 39-44.

[14] Lei, M., Shen, Z.Y., Li, Y.Q. and Luo, J.H., “Sectional Strength of Concrete-filled T-shaped Steel Tube Column Subjected to Axial Compression and Bending Moment”, Journal of Tongji University, 2016, Vol. 44, No. 3, pp. 348-354.