Structural Behavior and Load Distribution Factor of a T-Girder Bridge with Various Truss Diaphragms
Publication: Journal of Bridge Engineering
Volume 28, Issue 12
Abstract
A diaphragm is an essential component of a T-girder bridge. Evaluating the influence of various truss diaphragms (TDs) on the structural behavior and load distribution factor of T-girder bridges assists in bridge design and strengthening. In this study, a series of experiments and simulations were conducted to investigate the strengthening effect of two types of TDs (i.e., triangle-TDs and K-TDs) based on a small-scale T-girder bridge model. Formulas for the flexural rigidity of the two types of TDs were proposed and verified by using rigid-joint girder methods, experiments, and simulations. Then, taking the K-TD as an example, the calculation method for the stiffness of the truss was analyzed and derived based on rigid-joint girder and graphic multiplication methods. The results showed that K-TDs had a better strengthening effect than triangle-TDs. The deflection and strain of the K-TD-strengthened T-girder bridge were reduced by 21% and 16%, respectively, compared with those of the triangle-TD-strengthened bridge. The formulas for flexural rigidity were proposed and used to calculate the load distribution factor. The maximum error of the calculated load distribution factor was 16% compared with the simulation and experimental results. Moreover, the calculation method for the stiffness of the K-TDs was analyzed and obtained.
Practical Applications
Deterioration of multigirder bridges is getting worse due to the increasing traffic load and insufficient maintenance. Adding diaphragms to the existing bridges can improve the load distribution of multigirder bridges and reduce the maximum load of the girders. This work evaluated the influence of two types of truss diaphragms (triangle truss diaphragm and K truss diaphragm) on the load distribution of a T-girder bridge, and the results showed that the two types of truss diaphragms can reduce the maximum deflection and strain in the T-girder bridge effectively. The flexural rigidity formulas for the two types of truss diaphragm were proposed and proved to be accurate by comparing with experiments and finite-element methods. Moreover, the truss stiffness of the K truss diaphragm was derived by a graphic multiplication method. These formulas can be used by bridge engineers for new bridge designing or existing bridge strengthening in practical engineering.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
The authors thank Editage (www.editage.com) for English language editing.
References
Abendroth, R. E., F. W. Klaiber, and M. W. Shafer. 1995. “Diaphragm effectiveness in prestressed-concrete girder bridges.” J. Struct. Eng. 121 (9): 1362–1369. https://doi.org/10.1061/(ASCE)0733-9445(1995)121:9(1362).
Bares, R., and C. E. Massonnet. 1968. Analysis of beam grids and orthotropic plates by the Guyon–Massonnet–Bareš method. London: Lockwood.
Barr, P., and M. N. Amin. 2006. “Shear live-load distribution factors for I-girder bridges.” J. Bridge Eng. 11 (2): 197–204. https://doi.org/10.1061/(ASCE)1084-0702(2006)11:2(197).
Barr, P. J., M. O. Eberhard, and J. F. Stanton. 2001. “Live-load distribution factors in prestressed concrete girder bridges.” J. Bridge Eng. 6 (5): 298–306. https://doi.org/10.1061/(ASCE)1084-0702(2001)6:5(298).
Cai, C. S., A. Chandolu, and M. Araujo. 2009. “Quantification of intermediate diaphragm effects on load distributions of prestressed concrete girder bridges.” PCI J. 54 (2): 48–63. https://doi.org/10.15554/pcij.03012009.48.63.
Chaudhury, S. 2004. “Effect of connections between adjacent units on decked precast/prestressed concrete girder bridges.” In Proc., PCI NBC. Chicago, IL: Precast/Prestressed Concrete Institute (PCI).
Chen, C., C. Yang, Y. Pan, H. Zhang, and H. De Backer. 2021a. “Simulation and design considerations on transverse connection of prestressed concrete T-girder bridge.” Int. J. Steel Struct. 21 (4): 1182–1196. https://doi.org/10.1007/s13296-021-00495-w.
Chen, C., and C. Q. Yang. 2019. “Experimental and simulation studies on the mechanical performance of T-girder bridge strengthened with transverse connection.” J. Perform. Constr. Facil. 33 (5): 04019055. https://doi.org/10.1061/(ASCE)CF.1943-5509.0001318.
Chen, C., C. Q. Yang, Y. Pan, H. Zhang, and H. De Backer. 2021b. “Parameters analysis and design of transverse connection strengthening prestressed concrete T-girder bridge.” Struct. Concr. 22 (6): 3385–3395. https://doi.org/10.1002/suco.202100040.
Cheung, M. S., R. Jategaonkar, and L. G. Jaeger. 1986. “Effects of intermediate diaphragms in distributing live loads in beam-and-slab bridges.” Can. J. Civ. Eng. 13 (3): 278–292. https://doi.org/10.1139/l86-040.
Fan, L. C. 1986. Bridge engineering. [In Chinese.] Beijing: China Communications Press.
Hou, P., J. Yang, Y. Pan, C. Ma, W. Du, C. Yang, and Y. Zhang. 2022. “Experimental and simulation studies on the mechanical performance of concrete T-girder bridge strengthened with K-brace composite trusses.” Structures 43: 479–492. https://doi.org/10.1016/j.istruc.2022.06.069.
Hughs, E., and R. Idriss. 2006. “Live-load distribution factors for prestressed concrete, spread box girder bridge.” J. Bridge Eng. 11 (5): 573–581. https://doi.org/10.1061/(ASCE)1084-0702(2006)11:5(573).
Jalali, H. H., and S. Maleki. 2015. “Nonlinear behavior of concrete end diaphragms in straight slab-girder bridges.” Sci. Iran. 22 (3): 604–614.
Karnovsky, I. A., and O. Lebed. 2010. Advanced methods of structural analysis. Boston: Springer.
Kong, S. Y., L. D. Zhuang, M. X. Tao, and J. S. Fan. 2020. “Load distribution factor for moment of composite bridges with multi-box girders.” Eng. Struct. 215: 110716. https://doi.org/10.1016/j.engstruct.2020.110716.
Kuzmanovic, B. O., and M. R. Sanchez. 1986. “Lateral distribution of live loads on highway bridges.” J. Struct. Eng. 112 (8): 1847–1862. https://doi.org/10.1061/(ASCE)0733-9445(1986)112:8(1847).
Li, G. H., and D. Shi. 1987. Load distribution of highway bridge. [In Chinese.] Beijing: China Communications Press.
Li, L., and Z. J. John Ma. 2010. “Effect of intermediate diaphragms on decked bulb-tee bridge system for accelerated construction.” J. Bridge Eng. 15 (6): 715–722. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000108.
Li, L., Z. J. Ma, and R. G. Oesterle. 2010. “Improved longitudinal joint details in decked bulb tees for accelerated bridge construction: Fatigue evaluation.” J. Bridge Eng. 15 (5): 511–522. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000097.
Li, L. F., Z. H. Cheng, W. Feng, and X. H. Liu. 2020. “Study on the effect of unequal transverse bracing systems on the transverse load distribution of steel–concrete composite bridges.” [In Chinese.] J. Railway Sci. Eng. 17 (11): 2832–2839. https://doi.org/10.19713/j.cnki.43-1423/u.T20191137.
Li, Q. L. 2010. “The damage analysis and strengthening research.” Master’s thesis, School of Transportation, Wuhan Univ. of Technology.
Lin, C. S., and D. A. Vanhorn. 1968. The effect of midspan diaphragms on load distribution in a prestressed concrete box-beam bridge Philadelphia bridge. Bethlehem, PA: Lehigh Univ.
Luo, A. D., X. O. Wang, N. J. Zhou, and R. Y. Liu. 2008. “Breakage types and reinforcement for crossbeam of simply supported T beam.” J. HUST (Urban Sci. Ed.) 25 (1): 85–87.
Mensah, S. A., and S. A. Durham. 2014. “Live load distribution factors in two-girder bridge systems using precast trapezoidal U-girders.” J. Bridge Eng. 19 (2): 281–288. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000520.
MoC ( Ministry of Construction). 2007. Code for design of aluminum structures. GB 50429. Beijing: MoC.
Niu, Y., B. Liu, Y. Zhao, S. Rong, and P. Huang. 2014. “Diaphragm damage of precast concrete T-shape girder bridge: Analysis and strengthening.” Open Civ. Eng. J. 8 (1): 396–405. https://doi.org/10.2174/1874149501408010396.
Puckett, J. A., S. X. Huo, M. Jablin, and D. R. Mertz. 2011. “Framework for simplified live load distribution-factor computations.” J. Bridge Eng. 16 (6): 777–791. https://doi.org/10.1061/(ASCE)BE.1943-5592.0000285.
Ren, W. X., and I. E. Harik. 2002. “Modal analysis of the Cumberland River bridge on I-24 highway in west Kentucky.” In Proc., SPIE, 21–27. Los Angeles, CA: The International Society for Optical Engineering.
Shuai, T., K. M. Zhen, and S. Bo. 2020. “Anchoring the CFRP strengthening of concrete bridge decks: A comparison of methods.” Indian J. Eng. Mater. Sci. 27 (2): 288–299.
Sithichaikasem, S., and W. L. Gamble. 1972. Effects of diaphragms in bridges with prestressed concrete I-section girders. Bridge superstructures. Champaign, IL: Univ. of Illinois at Urbana-Champaign.
Snyder, M., and Y. F. Chen. 2014. “Development of aluminum diaphragms for concrete bridges.” In Proc., 9th Int. Conf. on Short and Medium Span Bridges. Montreal, QC: Canadian Society for Civil Engineering (CSCE).
Vanhorn, D. A., and C. H. Chen. 1971. Lateral distribution of load for bridges constructed with prestressed concrete I-beams. Washington, DC: Transportation Research Board.
Wu, C., and S. Z. Qiang. 2006. Modern steel bridge. Beijing: China Communications Press.
Wu, J. C., and F. Gao. 2015. “Analysis on prefabricated T-beam bridge diseases causes and construction measures.” Shaanxi Archit. 41 (5): 146–147. https://doi.org/10.13719/j.cnki.cn14-1279/tu.2015.05.083.
Yang, C., W. Du, P. Hou, F. Zhu, Y. Chen, C. Ma, Y. Pan, and H. Zhang. 2022. “Adding composite truss to improve mechanical properties of reinforced concrete T-girder bridge.” Adv. Struct. Eng. 25 (10): 2058–2075. https://doi.org/10.1177/13694332221086705.
Yang, L., and Z. D. Li. 2013. “Research on strengthening T-beam transverse connection in the highway bridge reinforcement design.” In Proc., Improving Multimodal Transportation Systems—Information, Safety, and Integration, 482–488. Reston, VA: ASCE.
Yao, X. F., and Y. Xu. 2010. “Experimental study on damage assessment of concrete T-beam bridges.” J. Highway Transp. Res. Dev. 4 (2): 62–66. https://doi.org/10.1061/JHTRCQ.0000293.
Zhang, R. B. 2017. “Case study on reinforcing hollow slab girder bridge by transverse steel girder method and transverse prestress method.” Shanxi Sci. Technol. Commun. 6 (12): 67–70.
Zhang, Y. Q. 2015. “Experimental research on lateral distribution factors of load on continuous T beam bridges at large and wide span ratio.” [In Chinese.] Technol. Highway Transp. 4: 75–79. https://doi.org/10.13607/j.cnki.gljt.2015.04.016.
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© 2023 American Society of Civil Engineers.
History
Received: Nov 13, 2022
Accepted: Jul 21, 2023
Published online: Sep 29, 2023
Published in print: Dec 1, 2023
Discussion open until: Feb 29, 2024
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