Advanced Steel Construction

Vol. 10, No. 4, pp. 385-403 (2014)



Fu Zhongqiu, Ji Bohai* , Maeno Hirofumi, Eizien A. and Chen Jiashu

College of Civil and Transportation Engineering, Hohai University, Nanjing 210098, China

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

Received: 28 September 2012; Revised: 24 March 2013; Accepted: 18 October 2013




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To study the flexural behaviour of lightweight aggregate concrete filled steel tubes (LACFST), 21 LACFST specimens and 8 steel tubes without filling concrete were tested under pure bending load. The parameters considered are: steel tube diameter and thickness, lightweight aggregate concrete (LAC) strength and shear span ratio. According to the test results, the failure mode, deflect ion and failure process were studied and their influence on the flexural behaviour of LACFST was analyzed. Several codes were used to calculate the stiffness and moment capacity. Based on the mechanical equilibrium and combined strength, two methods were provided to calculate the moment capacity in this paper. The calculated results were verified with the test ones. The constitutive model of confined LAC in compressive region was also proposed and used i n the FEM to analyze the flexural behaviour of LACFST. This study showed the strain distribution agreed with the Bernoulli-Euler’s theory. The deflection along the length distributed as half sine wave curve during the test. The moment capacity of LACFST increased as the steel ratio and LAC strength increased. But the shear span ratio had almost no influence on the flexural behaviour of LACFST. The comparison between the calculation and the test showed the results of AIJ (1997) for stiffness and DL/T5085 for moment capacity fitted with the test ones well. But the results using the two proposed methods had a better accuracy to calculate the moment capacity. The FEM analysis showed the constitutive model of confined LAC in compressive region was also proved having a good accuracy.



Lightweight aggregate concrete filled steel tube, flexural behaviour, stiffness, moment capacity, calculation method


[1] Ge, H.B., Susantha, K.A.S., Satake, Y., et al., “Seismic Demand Predictions of Cconcrete-filled Steel Box Columns”, Engineering Structures, 2003,Vol. 25, No. 3, pp. 337-345.

[2] Gao, S.B. and Ge, H.B., “Numerical Simulation of Hollow and Concrete-filled Steel Columns”, Advanced Steel Construction, 2007, Vol. 3, No. 3, pp. 668-678.

[3] Montejo, L.A., Gonzalez-Roman, L.A. and Kowalsky, M.J., “Seismic Performance Evaluation of Reinforced Concrete-Filled Steel Tube Pile/Column Bridge Bents”, Journal of Earthquake Engineering, 2012, Vol. 16, No. 3, pp. 401-424.

[4] Morcous, G., Hanna, K., Deng, Y., et al., “Concrete-Filled Steel Tubular Tied Arch Bridge System: Application to Columbus Viaduct ”, Journal of Bridge Engineering, 2012, Vol. 17, No. 1, pp. 107-116.

[5] Kang, J.Y., Choi, E.S., Chin, W.J., et al, “Flexural Behavior of Concrete-filled Steel Tube Members and its Application”, International Journal of Steel Structures, 2007, Vol. 7, No. 4, pp.319-324.

[6] Mossahebi, N., Yakel, A. and Azizinamini, A., “Experimental Investigation of a Bridge Girder made of Steel Tube Filled with Concrete”, Journal of Constructional Steel Research, 2005, Vol. 61, No. 3, pp. 371-386.

[7] Mohamed, H.M. and Masmoudi, R., “Flexural Strength and Behavior of Steel and FRP-reinforced Concrete-filled FRP Tube Beams”, Engineering Structures, 2010, Vol. 32, No. 11, pp. 3789-3800.

[8] Soundararajan, A. and Shanmugasundaram, K., “Flexural Behaviour of Concrete-Filled Steel Hollow Sections Beams”, Journal of Civil Engineering and Management, 2008, Vol.14, No. 2, pp. 107-114.

[9] Han, LH, “Flexural Behaviour of Concrete-filled Steel Tubes”, Journal of Constructional Steel Research, 2004, Vol. 60, No. 2, pp. 313-337.

[10] Deng, Y., Tuan, C.Y. and Xiao, Y., “Flexural Behavior of Concrete-Filled Circular Steel Tubes under High-Strain Rate Impact Loading”, Journal of Structural Engineering-ASCE, 2012, Vol. 138, No. 3, pp. 449-456.

[11] Nakamura, S., Momiyama, Y., Hosaka, T., et al., “New Technologies of Steel/Concrete Composite Bridges”, Journal of Constructional Steel Research, 2002, Vol. 58, No. 1, pp. 99-130.

[12] Ghannam, S, Jawad, Y.A. and Hunaiti, Y., “Failure of Lightweight Aggregate Concrete-Filled Steel tTubular Columns”, Steel and Composite Structures, 2004, Vol. 4, No. 1, pp. 1-8.

[13] Mouli, M. and Khelafi, H., “Strength of Short Composite Rectangular Hollow Section Columns Filled with Lightweight Aggregate Concrete”, Engineering Structures, 2007, Vol. 29, No. 8, pp. 1791-1797.

[14] Assi, I.M., Qudeimat, E.M. and Hunaiti, Y., “Ultimate Moment Capacity of Foamed and Lightweight Aggregate Concrete-filled Steel Tubes”, Steel and Composite Structures, 2003, Vol. 3, No. 3, pp. 199-212.

[15] Fu, Z.Q., Ji B.H, Lv, L. and Zhou, W.J., “The Behavior of Lightweight Aggregate Concrete Filled Steel Tube Slender Columns under Axial Compression”, Advanced Steel Construction, 2011, Vol. 7, No. 2, pp. 144-156.

[16] Elzien, A., Ji, B.H., Fu, Z.Q. and Hu, Z.Q, “The Behavior of Lightweight Aggregate Concrete Filled Steel Tube Columns under Eccentric Loading”, Steel and Composite Structures, 2011, Vol. 11, No. 6, pp. 469-488.

[17] Architectural Institute of Japan (AIJ), “Recommendations for Design and Construction of Concrete Filled Steel Tubular Structures”, 1997.

[18] British Standard Institute, “BS5400, Part 5, Concrete and Composite Bridges”, 1979.

[19] Eurocode 4, “Design of Composite Steel and Concrete Structures”, 1994.

[20] AISC, “Load and Resistance Factor Design Specification for Structural Steel Buildings”, 1999.

[21] Engineering Construction Standard of Fujian Province of China, “Technical Specification for Concrete-Filled Steel Tubular Structures”, 2003. (In Chinese)

[22] Electric Power Industry Standard of China, “Code for Design of Steel-Concrete Composite Structures”, 1999. (In Chinese)

[23] Fu, Z.Q., Ji B.H., Lv, L. and Yang M., “The Mechanical Properties of Lightweight Aggregate Concrete Constrained by Steel Tube”, Geotechnical Special Publication ASCE, 2011, No. 219, pp. 33-39.

[24] Fu, Z.Q., Ji B.H., Zhou, Y. and Wang X.L., “An Experimental Behavior of Lightweight Aggregate Concrete Filled Steel Tubular Stub under Axial Compression”, Geotechnical Special Publication ASCE, 2011, No. 219, pp. 24-32.

[25] Wang, P. T., Shah, S. P. and Naaman, A.E., “Stress-Strain Curves of Normal and Lightweight Concrete in Compression”, Journal of American Concrete Institute, 1978, Vol. 75, No. 11, pp. 603-611.

[26] Han, L.H., “Concrete Filled Steel Tube Structure - Theory and Application (Second Edition)”, Science Press, 2007. (In Chinese)