Fatigue Performance Test and Finite-Element Analysis of Concrete-Filled Steel-Tube K-Joints
Publication: Journal of Bridge Engineering
Volume 28, Issue 3
Abstract
To avoid fatigue cracking of K-joints in concrete-filled steel-tube (CFST) truss arch bridges, fatigue performance tests and finite-element analysis were conducted to investigate the hot spot stress distribution, fatigue performance evolution, and final fatigue failure pattern of the CFST K-joints. The results of a CFST K-joint were compared with those of a steel tube (ST) K-joint, to reveal the influence of concrete filled in a chord on the fatigue performance of the CFST K-joint. The results show that the hot spot stress of a CFST K-joint can be obtained by quadratic extrapolation. The stress concentration factor (SCF) on the chord side of the intersecting weld of CFST K-joints is larger than those on the brace side, and the maximum SCF is located at the crown point on the chord side of the intersecting weld connecting the tensioned brace to the chord. Because the constraint action of the core concrete improves the radial stiffness of the chord, making the section radial deformation of the CFST K-joint much smaller than that of the ST K-joint, the in-chord concrete could relieve the SCF of CFST K-joints by 19.5%–49.7%. Since the existing SCF calculation methods of ST K-joints and CFST K-joints do not consider the effect of in-chord concrete or the coupling effect of geometric parameters, they are not applicable to the SCF calculation of CFST K-joints. The fatigue crack growth process of a CFST K-joint can be divided into four stages: crack initiation, slow propagation, rapid propagation, and sharp fracture. The fatigue crack propagation speed of the CFST K-joint is obviously slower than that of the ST K-joint due to the effect of the in-chord concrete. The number of cycles corresponding to the 15% change of the peak dynamic strain is recommended as the fatigue life of the CFST K-joint. An S-N curve for fatigue life evaluation of CFST K-joints is proposed. Comparing with the fatigue test in this paper and existing fatigue test of other CFST joints, the proposed S-N curve for CFST K-joints has high precision and safety.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The authors would like to acknowledge the support from the National Key Research and Development Program of China (Grant No. 2017YFE0130300), the support from the National Natural Science Foundation of China (Grant No. 52078137), and the support from the Natural Science Foundation of Fujian Province (Grant No. 2019J06009).
References
Acevedo, C., and A. Nussbaumer. 2012. “Effect of tensile residual stresses on fatigue crack growth and S-N curves in tubular joints loaded in compression.” Int. J. Fatigue 36 (1): 171–180. https://doi.org/10.1016/j.ijfatigue.2011.07.013.
API (American Petroleum Institute). 2002. Recommended practice for planning, designing, and constructing fixed offshore platforms working stress design. RP 2A-WSD. Washington, DC: API.
Cao, Y., Z. Meng, S. Zhang, and H. Tian. 2013. “FEM study on the stress concentration factors of K-joints with welding residual stress.” Appl. Ocean Res. 43: 195–205. https://doi.org/10.1016/j.apor.2013.09.006.
CEN (European Committee for Standardization). 2005. Design of steel structures, part 1-9. Eurocode 3. Brussels, Belgium: CEN.
Chen, B., and T. Wang. 2009. “Overview of concrete filled steel tube arch bridges in China.” Pract. Period. Struct. Des. Constr. 14 (2): 70–80. https://doi.org/10.1061/(ASCE)1084-0680(2009)14:2(70).
Chen, K., H. Huang, Q. Wu, S. Nakamura, and B. Chen. 2019. “Experimental and finite element analysis research on the fatigue performance of CHS K-joints.” Eng. Struct. 197: 109365. https://doi.org/10.1016/j.engstruct.2019.109365.
CIDECT (Comité International pour le Développement et l’Etude de la Construction Tubulaire). 2001. Design guide for circular and rectangular hollow section joints under fatigue loading, part 8. Berlin: CIDECT.
Diao, Y., and W. Fan. 2013. “Experimental research on fatigue of tubular joints in concrete-filled steel tube.” [In Chinese.] Build. Struct. 43 (5): 45–47+17. https://doi.org/10.19701/j.jzjg.2013.05.009.
DNV (Det Norske Veritas). 2014. Fatigue design of offshore steel structures. DNVRP-C203. Høvik, Norway: DNV.
Gho, W. M., T. C. Fung, and C. K. Soh. 2003. “Stress and strain concentration factors of completely overlapped tubular K(N) joints.” J. Struct. Eng. 129 (1): 21–29. https://doi.org/10.1061/(ASCE)0733-9445(2003)129:1(21).
Han, L. 2018. Concrete-filled steel tubular structures - Theory and practice. 3rd ed. [In Chinese.] Beijing: Science Press.
IIW (International Institute of Welding). 1985. Recommended fatigue design procedure for hollow section joints: Part 1. IIW Doc. XV-582-85. Strasbourg, France: IIW.
Jin, D., C. Hou, L. Shen, and L. Han. 2019. “Numerical investigation of demountable CFST K-joints using blind bolts.” J. Constr. Steel Res. 160: 428–443. https://doi.org/10.1016/j.jcsr.2019.05.046.
JSSC (Japanese Society of Steel Construction). 2012. Fatigue design specification for steel structures. Tokyo: JSSC.
Karamanos, S. A., A. Romeijn, and J. Wardenier. 2000. “Stress concentrations in tubular gap K-joints: Mechanics and fatigue design.” Eng. Struct. 22 (1): 4–14. https://doi.org/10.1016/S0141-0296(98)00062-5.
Lan, X., Y. Huang, T. Chan, and B. Young. 2018. “Static strength of stainless steel K- and N-joints at elevated temperatures.” Thin-Walled Struct. 122: 501–509. https://doi.org/10.1016/j.tws.2017.10.009.
Morgan, M. R., and M. M. K. Lee. 1997. “New parametric equations for stress concentration factors in tubular K-joints under balanced axial loading.” Int. J. Fatigue 19 (4): 309–317. https://doi.org/10.1016/S0142-1123(96)00081-3.
Morgan, M. R., and M. M. K. Lee. 1998. “Parametric equations for distributions of stress concentration factors in tubular K-joints under out-of-plane moment loading.” Int. J. Fatigue 20 (6): 449–461. https:// doi.org/10.1016/S0142-1123(98)00011-5.
Musa, I. A., and F. R. Mashiri. 2019. “Stress concentration factor in concrete-filled steel tubular K-joints under balanced axial load.” Thin-Walled Struct. 139: 186–195. https://doi.org/10.1016/j.tws.2019.03.003.
Qian, X., K. Jitpairod, P. Marshall, S. Swaddiwudhipong, Z. Ou, Y. Zhang, and M. R. Pradana. 2014. “Fatigue and residual strength of concrete-filled tubular X-joints with full capacity welds.” J. Constr. Steel Res. 100: 21–35. https://doi.org/10.1016/j.jcsr.2014.04.021.
Sakai, Y., T. Hosaka, A. Isoe, A. Ichikawa, and K. Mitsuki. 2004. “Experiments on concrete filled and reinforced tubular K-joints of truss girder.” J. Constr. Steel Res. 60 (3–5): 683–699. https://doi.org/10.1016/S0143-974X(03)00136-6.
Shao, Y. 2007. “Geometrical effect on the stress distribution along weld toe for tubular T- and K-joints under axial loading.” J. Constr. Steel Res. 63 (10): 1351–1360. https://doi.org/10.1016/j.jcsr.2006.12.005.
Shao, Y., Z. Du, and S. Lie. 2009. “Prediction of hot spot stress distribution for tubular K-joints under basic loadings.” J. Constr. Steel Res. 65 (10–11): 2011–2026. https://doi.org/10.1016/j.jcsr.2009.05.004.
Tong, L., G. Xu, X. L. Zhao, H. Zhou, and F. Xu. 2019. “Experimental and theoretical studies on reducing hot spot stress on CHS gap K-joints with CFRP strengthening.” Eng. Struct. 201: 109828. https://doi.org/10.1016/j.engstruct.2019.109827.
Udomworarat, P., C. Miki, A. Ichikawa, M. Komechi, K. Mitsuki, and T. Hosaka. 2002. “Fatigue performance of composite tubular K-joints for truss type bridge.” Struct. Eng./Earthquake Eng. 19 (2): 65s–80s. https://doi.org/10.2208/jsceseee.19.65s.
Wang, K., L. Tong, J. Zhu, X. Zhao, and F. R. Mashiri. 2013. “Fatigue behavior of welded T-joints with a CHS brace and CFCHS chord under axial loading in the brace.” J. Bridge Eng. 18 (2): 142–152. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000331.
Yang, J., Y. Chen, and K. Hu. 2015. “Stress concentration factors of negative large eccentricity tubular N-joints under axial compressive loading in vertical brace.” Thin-Walled Struct. 96: 359–371. https://doi.org/10.1016/j.tws.2015.08.027.
Zheng, J., S. Nakamura, T. Okumatsu, and T. Nishikawa. 2019. “Formulation of stress concentration factors for concrete-filled steel tubular (CFST) K-joints under three loading conditions without shear forces.” Eng. Struct. 190: 90–100. https://doi.org/10.1016/j.engstruct.2019.04.017.
Zheng, J., and J. Wang. 2018. “Concrete-filled steel tube arch bridges in China.” Engineering 4 (1): 143–155. https://doi.org/10.1016/j.eng.2017.12.003.
Zhong, X., S. Yang, and W. Shi. 2011. “Experimental research on fatigue performance of CFST-K-joint.” [In Chinese.] Eng. Sci. 13 (9): 97–100.
Zhou, Y., X. Qian, A. Birnie, and X. Zhao. 2018. “A reference free ultrasonic phased array to identify surface cracks in welded steel pipes based on transmissibility.” Int. J. Press. Vessels Pip. 168: 66–78. https://doi.org/10.1016/j.ijpvp.2018.09.006.
Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 28 • Issue 3 • March 2023
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Apr 11, 2022
Accepted: Oct 23, 2022
Published online: Jan 13, 2023
Published in print: Mar 1, 2023
Discussion open until: Jun 13, 2023
ASCE Technical Topics:
- Composite materials
- Concrete
- Continuum mechanics
- Cracking
- Engineering fundamentals
- Engineering materials (by type)
- Engineering mechanics
- Fatigue (material)
- Fatigue life
- Fatigue tests
- Finite element method
- Fracture mechanics
- Joints
- Material mechanics
- Material properties
- Materials engineering
- Methodology (by type)
- Numerical methods
- Solid mechanics
- Structural engineering
- Structural members
- Structural systems
- Tubes (structure)
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.