This study investigates the structural behavior and flexural performance of concrete slabs incorporating recycled polyethylene terephthalate (PET) at dosages of 200 kg/m3 and 300 kg/m3 as a partial replacement for fine aggregate in the mixture. Eight slab specimens were cast and tested, including normal concrete (NC), PET-modified concrete, and reinforced concrete slabs, with thicknesses of 10 cm and 15 cm. The experimental program involved flexural load testing to determine the first crack load, ultimate failure load, deflection, and crack patterns. The results revealed that increasing PET content improved ductility and first crack resistance, with the PET (300 kg/m3) slabs exhibiting the highest deflection capacity and more distributed, narrower cracks compared to normal concrete. Although PET addition reduced compressive strength, especially at higher dosages, it enhanced flexural toughness. Reinforced concrete slabs demonstrated the highest load-bearing capacity and deflection, confirming their superior structural performance. The study highlights that PET inclusion can contribute positively to crack control and sustainability by recycling plastic waste into structural elements. Incorporating recycled PET into concrete not only enhances structural performance but also supports environmental sustainability by reducing plastic waste, conserving natural resources, and lowering the environmental footprint of construction. Overall, PET-modified concrete presents a viable, eco-friendly solution for improving the flexural behavior of slabs, particularly in applications with limited or no reinforcement.
FarajRHHama AliHFSherwaniAFH, et al.Use of recycled plastic in self-compacting concrete: a comprehensive review on fresh and mechanical properties. J Build Eng2020; 30: 101283.
11.
SaikiaNDe BritoJ. Waste polyethylene terephthalate as an aggregate in concrete. Mater Res2013; 16: 341–350.
12.
PET Resin Association. Fact sheet—An introduction to PET (polyethylene terephthalate). Richmond, Virginia, United States: PETRA, 2015.
13.
SayınCÖErenÖ. Physical and durability properties of recycled polyethylene terephthalate fibre reinforced concrete. Eur J Environ Civ Eng2021; 26: 7084–7102.
14.
AmranYMAlyousefRAlabduljabbarH, et al.Clean production and properties of geopolymer concrete: a review. J Cleaner Prod2020; 251: 119679.
15.
BashaSMReddyCBVasugiK. Strength behaviour of geopolymer concrete replacing fine aggregates by M-sand and E-waste. Int J Eng Trends Technol2016; 40: 401–407.
16.
BhardwajBKumarP. Waste foundry sand in concrete: a review. Constr Build Mater2017; 156: 661–674.
17.
AhmedHUMohammedASQaidiSMA, et al.Compressive strength of geopolymer concrete composites: a systematic comprehensive review, analysis and modeling. Eur J Environ Civ Eng2022; 27: 1–46.
18.
TorresASimoniMUKeidingJK, et al.Sustainability of the global sand system in the Anthropocene. One Earth2021; 4: 639–650.
19.
FilhoWLHuntJLingosA, et al.The unsustainable use of sand: reporting on a global problem. Sustainability2021; 13: 1–16.
20.
FigueiredoFda SilvaPBoteroER, et al.Concrete with partial replacement of natural aggregate by PET aggregate—an exploratory study about the influence in the compressive strength. AIMS Mater Sci2022; 9: 172–183.
21.
MastanMMAsadiSS. Effect of waste plastic as fine aggregate replacement on properties of concrete. Int J Civ Eng Technol2017; 8: 1588–1594.
22.
FarajRHSherwaniAFHDaraeiA. Mechanical, fracture and durability properties of self-compacting high strength concrete containing recycled polypropylene plastic particles. J Build Eng2019; 25: 100808.
23.
QaidiS. Behaviour of concrete made of recycled waste PET and confined with CFRP fabrics. MSc Thesis, University of Duhok, Iraq, 2021.
24.
JosephPTretsiakova-McNallyS. Sustainable non-metallic building materials. Sustainability2010; 2: 400–427.
SaxenaRSiddiqueSGuptaT, et al.Impact resistance and energy absorption capacity of concrete containing plastic waste. Constr Build Mater2018; 176: 415–421.
27.
Abu-SaleemMZhugeYHassanliR, et al.Impact resistance and sodium sulphate attack testing of concrete incorporating mixed types of recycled plastic waste. Sustainability2021; 13(7): 1–18.
28.
SaxenaRGuptaTSharmaRK, et al.Assessment of mechanical and durability properties of concrete containing PET waste. Sci Iran2020; 27: 1–9.
29.
DeramanRNawiMNMYasinMN, et al.Polyethylene terephthalate waste utilisation for production of low thermal conductivity cement sand bricks. J Adv Res Fluid Mech Therm Sci2021; 88(3): 117–136. https://doi.org/10.37934/arfmts.88.3.117136
30.
DawoodAOAl-KhazrajiHFalihRS. Physical and mechanical properties of concrete containing PET wastes as a partial replacement for fine aggregates. Case Stud Const Mater2021; 14: e00482.
31.
BamigboyeGOTarverdiKWaliES, et al.Effects of dissimilar curing systems on the strength and durability of recycled PET-modified concrete. Silicon2022; 14: 1039–1051.
32.
IslamMJMeherierMSIslamAKMR. Effects of waste PET as coarse aggregate on the fresh and hardened properties of concrete. Constr Build Mater2016; 125: 946–951.
33.
HaqueR. Performance of partially replaced plastic bottles (PET) as coarse aggregate in producing green concrete. Brill Eng2021; 2: 15–19.
34.
Sai GopiKSrinivasDTRajuVSP. Feasibility study of recycled plastic waste as fine aggregate in concrete. In: E3S Web of Conferences, 2020.
35.
ChongBWShiX. Meta-analysis on PET plastic as concrete aggregate using response surface methodology and regression analysis. J Infrastruct Preserv Resilience2023; 4: 1–15. DOI: 10.1186/s43065-022-00069-y
36.
AlmeshalITayehBAlyousefR, et al.Eco-friendly concrete containing recycled plastic as a partial replacement for sand. J Mater Res Technol2020; 9: 4631–4643.
37.
BamigboyeGOTarverdiKUmorenA, et al.Evaluation of eco-friendly concrete having waste PET as fine aggregates. Clean Mater2021; 2: 100026.
38.
Al-HadithiAIAl-AniAK. Influence of recycled PET aggregates on the properties of concrete. J Constr Eng Manag2018; 144: 04018007.
39.
DawoodETAljazaeriZTMussaQA. Effect of recycled plastic aggregates on the mechanical properties of concrete. Case Stud Constr Mater2021; 15: e00757.
40.
ShubbarAAAl-ShadeediAS. The effect of using recycled PET aggregates on concrete properties. Int J Eng Technol2017; 9: 1201–1208.
41.
RahmaniEDehestaniMBeygiMHA, et al.On the mechanical properties of concrete containing waste PET particles. Constr Build Mater2013; 47: 1302–1308.
42.
MermerdaşKYilmazEAydinS. Performance of concrete with waste PET aggregate. Mater Today Proc2017; 4: 7993–8001.
43.
ShahSPatankarS. Properties of recycled PET and its applications in concrete. J Mater Civ Eng2019; 31: 04019150.
44.
CallisterWDRethwischDG. Materials science and engineering: An introduction. 10th ed. Hoboken, New Jersey, United States: Wiley, 2018.
45.
GorassiniA, et al.PET: structure, properties, and applications. Polym Degrad Stab2019; 165: 54–62.
46.
AwajaFPavelD. Recycling of PET. Eur Polym J2005; 41: 1453–1477.
47.
ASTM C39/C39M-23. Standard test method for compressive strength of cylindrical concrete specimens. West Conshohocken, Pennsylvania, United States: ASTM International, 2023.
48.
ASTM C78/C78M-22. Standard test method for flexural strength of concrete. West Conshohocken, Pennsylvania, United States: ASTM International, 2022.
49.
American Concrete Institute. ACI 544.1R-16: Guide for specifying, proportioning, and production of fiber-reinforced concrete. 2016.
50.
American Concrete Institute. ACI 544.4R-14: Fiber-reinforced concrete—Fiber materials. 2014.
51.
British Standards Institution. BS EN 206: Concrete—Specification, performance, production and conformity. 2016.
52.
RILEM Technical Committee. Use of recycled plastic waste in concrete applications. 2020.
53.
Egyptian Code for Design and Construction of Concrete Structures. ECP 203. Cairo, Egypt, 2020.
54.
BaeraCSzilagyiHMirceaC, et al.Concrete structures under impact loading: General aspects. Urbanism Archit Constr2016; 7: 239–250.
