Flexural and Shear Strength of RC Beam with Embedded Polystyrenes
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Abstract
This study examines the structural performance and material efficiency of reinforced concrete (RC) beams embedded with trapezoidal polystyrene, tested under flexural and shear loadings. The integration of polystyrene aims to reduce concrete volume while maintaining structural integrity. Twelve specimens were tested under four-point static loading, including five different polystyrene configurations and one control specimen for each loading type. Performance was evaluated based on load-displacement behavior, structural capacity, and material efficiency (i.e., strength gain vs concrete volume reduction). Results indicate that beams incorporating polystyrene remain functional. However, not all configurations increased load-bearing capacity; for example, PB5 showed decreased capacity. Performance is significantly influenced by the geometry of the embedded polystyrene, with increasing width having a more detrimental effect than depth. Among the specimens, PB2 exhibited the best overall performance, achieving 10% higher flexural capacity and 18% greater shear capacity despite a 10% reduction in concrete volume, resulting in 22% and 31% higher material efficiency under flexural and shear loadings, respectively. Some specimens, such as PB5, showed decreased capacity. These gains, however, were offset by lower cracking resistance and reduced ductility, which could limit the beam’s serviceability and affect its suitability for structural applications requiring high deformation capacity or crack control. Despite its potential, the use of polystyrene in RC beams presents practical challenges, including the study’s limited replication, construction complexity, and fire safety concerns, which must be addressed before broader implementation in structural applications.
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[2] Y.T. Lim, J.H. Ling, J.W. Lau, T.T.L. Danson, “Performance of reinforced concrete beam with polystyrene blocks at various regions,” Journal of Science and Applied Engineering, vol. 3, no. 2, pp. 62–71, 2021, doi: 10.31328/jsae.v3i2.1655.
[3] Y.T. Lim, J.H. Ling, H.T. Sia, L.W. Kam, J.T.S. Ngu, “Improvement in the reinforced concrete beam with embedded polystyrene under static load,” Indonesian Journal of Computing, Engineering, and Design, vol. 5, no. 2, pp. 67–77, 2023, doi: 10.35806/ijoced.v5i2.331.
[4] J.W. Lau, J.H. Ling, Y.T. Lim, “Feasibility study of reinforced concrete beam with embedded polystyrene spheres under incremental flexural load,” Borneo Journal of Science and Technology, vol. 2, no. 2, pp. 11–26, 2020. [Online]. Available: https://journal.uts.edu.my/Home/ArticleDownload?articleId=BJOST020204
[5] Y.T. Lim, J.H. Ling, J.W. Lau, A.Y.M. Yik, “Experimental study on the flexural behavior of reinforced polystyrene blocks in concrete beams,” Journal of the Civil Engineering Forum, vol. 7, no. 2, pp. 197–208, 2021, doi: 10.22146/jcef.62346.
[6] Y.T. Lim, J.H. Ling, “Incorporating lightweight materials in reinforced concrete beams and slabs – A review,” Borneo Journal of Sciences and Technology, vol. 1, no. 2, pp. 16–26, 2019. [Online]. Available: https://journal.uts.edu.my/Home/ArticleDownload?articleId=BJOST010203
[7] L. Ragavi, “Behaviour of reinforced concrete hollow beams under monotonic loading,” World Journal of Technology, Engineering and Research, vol. 2, no. 1, pp. 127–136, 2017.
[8] A.J.H. Alshimmeri, H.N.G. Al-Maliki, “Structural behavior of reinforced concrete hollow beams under partial uniformly distributed load,” Journal of Engineering, vol. 20, no. 7, pp. 130–145, 2014, doi: 10.31026/j.eng.2014.07.09.
[9] T.S. Al-Gasham, A.N. Hilo, M.A. Alawsi, “Structural behavior of reinforced concrete one-way slabs voided by polystyrene balls,” Case Studies in Construction Materials, vol. 11, pp. 1–13, 2019, doi: 10.1016/j.cscm.2019.e00292.
[10] S. Inoue, N. Egawa, “Flexural and shear behaviour of reinforced concrete hollow beams under reversed cyclic loads,” in Proc. Eleventh World Conference on Earthquake Engineering, 1996.
[11] T.S.S. Al-Gasham, “Reinforced concrete moderate deep beams with embedded PVC pipes,” Wasit Journal of Engineering Science, vol. 3, no. 1, pp. 19–28, 2015, doi: 10.31185/ejuow.Vol3.Iss1.32.
[12] J.H. Ling, J.W. Lau, Y.T. Lim, “Structural behaviour of reinforced concrete beam with embedded polystyrene spheres,” Civil and Sustainable Urban Engineering, vol. 3, no. 1, pp. 25–39, 2023, doi: 10.53623/csue.v3i1.180.
[13] D.T.L. Tan, J.H. Ling, “Flexural behaviour of reinforced concrete beam embedded with different alignment of polystyrene,” Borneo Journal of Sciences and Technology, vol. 2, no. 1, pp. 13–18, 2019. [Online]. Available: https://journal.uts.edu.my/Home/ArticleDownload?articleId=BJOST020104
[14] N. Mohamad, W.I. Goh, A.A.A. Samad, A. Lockman, A. Alalwani, “Structural behaviour of beam with HDPE plastic balls subjected to flexural load,” Materials Science Forum, vol. 889, pp. 270–274, 2017, doi: 10.4028/www.scientific.net/MSF.889.270
[15] B. Mosley, J. Bungey, R. Hulse, Reinforced Concrete Design to Eurocode 2, 7th ed., Palgrave Macmillan, England, 2012.
[16] British Standard, Eurocode 2: Design of Concrete Structures – Part 1-1: General Rules and Rules for Buildings, BS-EN 1992-1-1:2004, 2004.
[17] J.H. Ling, J.W. Lau, Y.T. Lim, “Behaviour of RC beam-slab member with embedded polystyrene spheres,” Journal of Civil Engineering, vol. 40, no. 1, pp. 3–11, 2025, doi: 10.12962/j20861206.v40i1.19650.
[18] R. Park, “Ductility evaluation from laboratory and analytical testing,” in Proc. Ninth World Conference on Earthquake Engineering, Tokyo-Kyoto, Japan, 1988, pp. 605–616. [Online]. Available: https://www.iitk.ac.in/nicee/wcee/article/9_vol8_605.pdf
[19] C. Bailey, T. Bull, A. Lawrence, “The bending of beams and the second moment of area,” The Plymouth Student Scientist, vol. 6, no. 2, pp. 328–339, 2013, doi: 10.24382/8z3x-cx21.
[20] M. Qin, X. Hu, J. Guo, “Preparation of a new type of expansion flame retardant and application in polystyrene,” Coatings, vol. 13, no. 4, pp. 733, 2023, doi: 10.3390/coatings13040733.
[21] J.L. Gurman, L. Baier, B.C. Levin, “Polystyrenes: A review of the literature on the products of thermal decomposition and toxicity,” Fire and Materials, vol. 11, no. 3, pp. 109–130, 1987, doi: 10.1002/fam.810110302.
[22] J.H. Ling, A.B. Abd. Rahman, I.S. Ibrahim, Z. Abdul Hamid, “An experimental study of welded bar sleeve wall panel connection under tensile, shear, and flexural loads,” International Journal of Concrete Structures and Materials, vol. 11, pp/ 525–540, 2017, doi: 10.1007/s40069-017-0202-y.
[23] J.H. Ling, A.B. Abd. Rahman, I.S. Ibrahim, “Deformation behavior of grouted sleeve wall connector under shear load in precast process of concrete wall.” Indonesian Journal of Computing, Engineering, and Design, vol. 4, pp. 1‒14, (2022), doi: 10.35806/ijoced.v4i2.263.
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