مجله ی مهندسی عمران شریف

مجله ی مهندسی عمران شریف

بررسی پارامترهای مؤثر بر پیوستگی و رفتار بیرون‌کشیدگی طناب‌های پلی‌اتیلن ترفتالات از کامپوزیت‌های سیمانی مسلح الیافی فولادی

نوع مقاله : یادداشت فنی

نویسندگان
رضا اکبری فر
علیرضا مرتضایی
علی بابایی
گروه مهندسی عمران، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران.
10.24200/j30.2025.67085.3436
چکیده
در پژوهش حاضر، رفتار پیوستگی طناب‌های بافته‌شده از پلی‌اتیلن ترفتالات (PET) بازیافتی به‌عنوان جایگزینی برای میلگرد فولادی در کامپوزیت‌های الیافی (FRCC) بررسی شده است. برای این منظور، بر روی نمونه‌های آزمایشگاهی FRCC با درصدهای مختلف الیاف فولادی، آزمون‌های بیرون‌کشیدگی مطابق با استاندارد 6RILEM RC بر روی میلگرد فولادی و طناب PET با قطر یکسان انجام شده و نتایج نشان داده است که نیروی بیرون‌کشیدگی برای میلگرد، حدود 30 کیلو‌نیوتن و برای PET، حدود 6/7کیلو‌نیوتن بوده است، که بیانگر کاهش 75 درصدی مقاومت چسبندگی PET است. با این‌ حال، میزان جابجایی متناظر با بیشینه‌ی بار در PET حدود 5/23 میلی‌متر و در میلگرد فولادی، 6/0میلی‌متر بوده است؛ که نشان‌دهنده‌ی 40 برابری افزایش شکل‌پذیری PET در مقایسه با میلگرد است. در تمامی نمونه‌ها، PET دچار گسیختگی شده و از بتن خارج نشده است، در حالی ‌که میلگردها با لغزش از بتن جدا شده‌اند. نتایج به‌دست‌آمده نشان داده است که با وجود مقاومت کمتر طناب PET در برابر کشش، رفتار پیوستگی آن به‌ویژه در نواحی با نیاز به شکل‌پذیری بالا، می‌تواند در طراحی‌های خاص استفاده شود.
کلیدواژه‌ها
کامپوزیت سیمانی مسلح الیافی (FRCC)
پلی‌اتیلن ترفتالات (PET)
طناب پلیمری بازیافتی
رفتار بیرون‌کشیدگی
پیوستگی بتن و میلگرد
موضوعات

عنوان مقاله English

Investigation of Parameters Affecting Bond Strength and Pull-Out Behavior of Polyethylene Terephthalate Ropes in Steel Fiber-Reinforced Cementitious Composites

نویسندگان English

Reza Akbarifar
Alireza Mortezaei
Ali Babaei
Department of Civil Engineering, Semnan branch, Islamic Azad University, Semnan, Iran
چکیده English

This study investigates the bond behavior of braided ropes made from recycled polyethylene terephthalate (PET) as a potential alternative to conventional steel reinforcement in fiber-reinforced cementitious composites (FRCC). Pull-out tests were conducted according to RILEM RC6 standards on FRCC specimens containing different volume fractions of steel fibers, using steel rebars and PET ropes with equal diameters (14 mm). The experimental results revealed that the maximum pull-out force was approximately 30 kN for steel bars and 7.6 kN for PET ropes, indicating a 75% reduction in bond strength for PET compared to steel. However, the displacement corresponding to the peak load was about 23.5 mm for PET ropes and only 0.6 mm for steel bars, representing a 40-fold increase in ductility for PET.
In all experiments, PET ropes failed internally without being pulled out from the matrix, while steel bars exhibited bond-slip failure.
The inclusion of steel fibers in the matrix significantly enhanced the bond performance, especially in terms of energy absorption and post-peak ductility.
For instance, in specimens containing 1% steel fibers, the maximum pull-out load of the PET ropes reached 7.6 KN at a displacement of 9.3 mm, showing a clear improvement over fiberless samples.
The experimental observations were further analyzed by comparing the bond–slip responses of PET and steel reinforcements, which demonstrated that PET exhibits a gradual softening after peak load instead of a brittle bond loss. This characteristic suggests a more stable and energy-dissipating interfacial mechanism. In addition, the use of recycled PET not only provides a sustainable and eco-friendly reinforcement option but also contributes to reducing construction waste and CO₂ emissions. Such properties make PET ropes particularly suitable for structures requiring high ductility and seismic resilience. The findings of this study can serve as a reference for future modeling of PET–concrete interface behavior and for developing design guidelines for sustainable fiber-reinforced composites.

کلیدواژه‌ها English

Recycled pet rope
fiber-reinforced cementitious composites (FRCC)
pull-out test
bond behavior
steel fiber
ductility
sustainable reinforcement
 
1.   da Silva Neto, J. T., Soares Junior, P. R. R., Reis, E. D., Maciel, P. S. S., Gomes, P. C. C., Gouveia, A. M. C. and Bezerra, A. C. S., 2025. Fiber-reinforced cementitious composites: recent advances and future perspectives on key properties for high-performance design. Discover Civil Engineering, 2(1), pp.1-20. https://doi.org/10.1007/s44290-025-00209-9
 
2.  Ahmed, S. and Ali, M., 2025. Investigation on pullout and shear behavior of recycled plastic rebar-concrete connection for mortar-free housing. Journal of Building Engineering, 114, 114266. https://doi.org/10.1016/j.jobe.2025.114266.
3. Overhage, V., Heins, K., Kimm, M., Ryu, G., You, Y. J., Kim, H.-Y. and Gries, T., 2024. Investigation of pull-out and mechanical performance of fibre reinforced concrete with recycled carbon fibres. Materials and Structures, 57, 140.      https://doi.org/10.1617/s11527-024-02453-4.
4.  Jouyandeh, R. T., Hemmati, A. and Mortezaei, A., 2023. Using woven recycled plastic fibers in reinforced concrete beams. Construction and Building Materials, 404, 133262.   https://doi.org/10.1016/j.conbuildmat.2023.133262.
5.  Bai, Y.-L., Tang, Z.-K. and Mei, S.-J., 2024. Experimental study on shear performance of PET FRP-strengthened RC beams without stirrups. Case Studies in Construction Materials, 20, e03272.https://doi.org/10.1016/j.cscm.2024.e03272.
 
6.    Zeng, J.-J., Sun, H.-Q., Xia, J.-R., Zhao, S., Feng, Z., Zhao, B. and Zhou, J.-K., 2025. Bond behavior between concrete and thermoplastic GFRP bars with novel surface features. Engineering Structures, 343, 121161. https://doi.org/10.1016/j.engstruct.2025.121161
 
7.    Makul, N., 2021. Principles of cement and concrete composites. Springer Nature, Cham, Switzerland.
 
8.   Gencel, O., Karadag, O., Oren, O. H. and Bilir, T., 2021. Steel slag and its applications in cement and concrete technology: A review. Construction and Building Materials, 283, pp.34-56. https://doi.org/10.1016/j.conbuildmat.2021.122783.
 
9.  Yuan, Z. and Jia, Y., 2021. Mechanical properties and microstructure of glass fiber and polypropylene fiber reinforced concrete: an experimental study. Construction and Building Materials, 266, pp.12-35. https://doi.org/10.1016/j.conbuildmat.2020.121048.
 
10.   Takasago, S., Kanakubo, T., Kobayashi, H. and Sasaki, H., 2023. Bond and cracking characteristics of PVA-fiber-reinforced cementitious composite reinforced with braided AFRP bars. Fibers, 11(12), pp.107.https://doi.org/10.3390/fib11120107
 
11.   Ashrafian, A., Berenjian, J. and Asghari Tilaki, F., 2020. Optimization of mixture proportions of self-compacted fiber reinforced concrete incorporating polypropylene using genetic and crow search algorithms. Modares Civil Engineering Journal, 20(3), pp.1-12 [In Persian]. https://20.1001.1.24766763.1399.20.3.11.1
 
12.  Gholhaki, M., Pachideh, G. and Rezayfar, O., 2017. An experimental study on mechanical properties of concrete containing steel and polypropylene fibers at high temperatures. Journal of Structural and Construction Engineering, 4(3), pp.167-179 [In Persian].   https://doi.org/10.22065/jsce.2017.77392.1072
13. Esmaeili, J., Sharifi, I., Andalibi, K. and Kasaei, J., 2017. Effect of different matrix compositions and micro steel fibers on tensile behavior of textile reinforced concrete. IOP Conference Series: Materials Science and Engineering, 246, 012031. doi:10.1088/1757-899X/246/1/012031
14.   kbarifar, R., Mortezaei, A. and Babaei, A., 2024. Meso-scale study of bond behavior between ribbed steel rebar and fiber-reinforced cementitious composite considering rebar rib geometry. Periodica Polytechnica: Civil Engineering, 68(4), pp.1350-1366. https://doi.org/10.3311/PPci.28772
 
15.  Kamani, R., Kamali Dolatabadi, M., Asghharian Jeddi, A. A. and Nasrollahzadeh, K., 2019. Increasing the efficiency of carbon fiber bundles in reinforcing fine grained concrete: An experimental study of flexural bearing capacity. Journal of Science and Technology of Composites, 6(2), pp.310-318 [In Persian]. 10.22068/jstc.2018.85673.1441
 
16.  Hajforoush, M., Kheyroddin, A. and Rezaifar, O., 2020. The effect of magnetic field on bond strength between reinforcing steel bar and steel fiber reinforced concrete by means of pull-out test. Concrete Research, 13(4), pp.5-16 [In Persian]. https://doi.org/10.22124/jcr.2020.17734.1448.
 
17.   Wang, Y., Li, Z., Zhang, C., Wang, X., Li, J., Liang, Y. and Chu, S., 2021. Bond behavior of BFRP bars with basalt-fiber reinforced cement-based composite materials. Structural Concrete, 22(1), pp.154-167. https://doi.org/10.1002/suco.201900548.
 
18.   Lin, A. and Ostertag, C. P., 2021. Interaction between high performance fiber reinforced cement-based composites and steel reinforcement. Engineering Structures, 247, pp.113-123. https://doi.org/10.1016/j.engstruct.2021.113173.
 
19. Zhou, Z. and Qiao, P., 2018. Bond behavior of epoxy-coated rebar in ultra-high performance concrete. Construction and Building Materials, 182, pp.406-417. https://doi.org/10.1016/j.conbuildmat.2018.06.113
 
20.  Khaksefidi, S., Ghalehnovi, M. and de Brito, J., 2021. Bond behaviour of high-strength steel rebars in normal (NSC) and ultra-high performance concrete (UHPC). Journal of Building Engineering, 33, pp.34-57. https://doi.org/10.1016/j.jobe.2020.101592.
 
21.   Chao, S.-H., Naaman, A. E. and Parra-Montesinos, G. J., 2006. Bond behavior of strand embedded in fiber reinforced cementitious composites. Strain, 50(2), pp.56-71. https://doi.org/10.1111/j.1475-1305.2008.00562.x.
 
22.    RILEM-CEB-FIP-RC6, 1983. Recommendation RC 6: Bond test for reinforcement steel. 2. Pull-out test. Georgi Publishing Company, Paris, France.
23. Carvalho, E. P., Ferreira, E. G., Cunha, J. C. d., Rodrigues, C. S. and Maia, N. S., 2017. Experimental investigation of steel-concrete bond for thin reinforcing bars. Latin American Journal of Solids and Structures, 14(11), pp.1932-1951.     https://doi.org/10.1590/1679-78254116
 
 
 
مجله ی مهندسی عمران شریف
دوره 42، شماره 1 - شماره پیاپی 1
مقالات شماره بهار در حال بارگذاری می باشد
بهار 1405
صفحه 117-126