Title:
Effect of Bond Condition on Cyclic Behavior of Post- Tensioned Concrete Beams with Carbon Fiber-Reinforced Polymer Tendons
Author(s):
Fei Peng, Weichen Xue, and Shulu Zhang
Publication:
Structural Journal
Volume:
121
Issue:
2
Appears on pages(s):
153-163
Keywords:
carbon fiber-reinforced polymer (CFRP); cyclic behavior; ductility; partially bonded; prestressed concrete beam
DOI:
10.14359/51740251
Date:
3/1/2024
Abstract:
The lack of ductility is the main concern in the use of carbon
fiber-reinforced polymer (CFRP) reinforcement as prestressing
tendon in concrete members. To address this concern, a partially
bonded concept has been proposed. In this approach, CFRP
tendons are intentionally debonded from the concrete in the middle
region of the prestressed concrete beam, while remaining bonded
at each end. In this study, eight post-tensioned beams, including
five beams with CFRP tendons and three beams with steel tendons,
are tested under cyclic loading. Three bond conditions, including
fully bonded, partially bonded, and fully unbonded, are considered.
The results indicate that increasing the unbonded length of the
tendon changed the failure mode from CFRP rupture to concrete
crushing. There is a trend that the flexural capacity decreased with
the increase of the unbonded length. The displacement ductility
(μ) of partially bonded CFRP prestressed beams ranged from 5.38
to 5.70, which is significantly higher than that of the fully bonded
beam (μ = 2.83) and slightly lower than that of the fully unbonded
beam (μ = 6.10). Finally, by introducing a relative bond length
coefficient into the ultimate tensile stress equation for internally
unbonded tendons, a modified design approach for estimating
flexural capacities of the partially bonded beams is proposed. The
experimental flexural capacities are in close agreement with the
values predicted using the modified design approach.
Related References:
ACI Committee 440, 2004, “Prestressing Concrete Structures with FRP Tendons (ACI 440.4R-04),” American Concrete Institute, Farmington Hills, MI, 35 pp.
ASTM D7205-21, 2021, “Standard Test Method for Tensile Properties of Fiber Reinforced Polymer Matrix Composite Bars,” ASTM International, West Conshohocken, PA, 13 pp.
Au, F. T. K., and Du, J. S., 2008, “Deformability of Concrete Beams with Unbonded FRP Tendons,” Engineering Structures, V. 30, No. 12, pp. 3764-3770. doi: 10.1016/j.engstruct.2008.07.003
Chen, C.; Chen, J.; Zhou, Y.; Sui, L.; and Hu, B., 2021, “Design of Ductile H-Anchorage for Strengthening Reinforced Concrete Beams with Prestressed FRP,” Construction and Building Materials, V. 307, Nov., p. 124883. doi: 10.1016/j.conbuildmat.2021.124883
Choi, H. T.; West, J. S.; and Soudki, K. A., 2011a, “Effect of Partial Unbonding on Prestressed Near-Surface-Mounted CFRP-Strengthened Concrete T-Beams,” Journal of Composites for Construction, ASCE, V. 15, No. 1, Feb., pp. 93-102. doi: 10.1061/(ASCE)CC.1943-5614.0000149
Choi, H. T.; West, J. S.; and Soudki, K. A., 2011b, “Partially Bonded Near-Surface-Mounted CFRP Bars for Strengthened Concrete T-Beams,” Construction and Building Materials, V. 25, No. 5, May, pp. 2441-2449. doi: 10.1016/j.conbuildmat.2010.11.056
Dorian, P. T., 2002, “Deformability and Ductility of Partially-Prestressed Concrete Beams Containing CFRP/Stainless Steel Reinforcements,” master’s dissertation, Queen’s University, Kingston, ON, Canada, 255 pp.
Fischer, G., and Li, V. C., 2003, “Deformation Behavior of Fiber-Reinforced Polymer Reinforced Engineered Cementitious Composite (ECC) Flexural Members under Reversed Cyclic Loading Conditions,” ACI Structural Journal, V. 100, No. 1, Jan.-Feb., pp. 25-35.
GB/T 50081, 2019, “Standard for Test Methods of Concrete Physical and Mechanical Properties (GB/T 50081-2019),” China Architecture & Building Press, Beijing, China, 103 pp.
GB/T 50152, 2012, “Standard for Test Method of Concrete Structures (GB/T 50152-2012),” China Architecture & Building Press, Beijing, China, 119 pp.
Grace, N. F., and Abdel-Sayed, G., 1998, “Ductility of Prestressed Concrete Bridges Using CFRP Strands,” Concrete International, V. 20, No. 6, June, pp. 25-30.
Grace, N. F.; Ushijima, K.; Matsagar, V.; and Wu, C., 2013, “Performance of AASHTO-Type Bridge Model Prestressed with Carbon Fiber-Reinforced Polymer Reinforcement,” ACI Structural Journal, V. 110, No. 3, May-June, pp. 491-501.
Heo, S.; Shin, S.; and Lee, C., 2013, “Flexural Behavior of Concrete Beams Internally Prestressed with Unbonded Carbon-Fiber-Reinforced Polymer Tendons,” Journal of Composites for Construction, ASCE, V. 17, No. 2, Apr., pp. 167-175. doi: 10.1061/(ASCE)CC.1943-5614.0000306
Jeong, Y.; Kim, W. S.; Gribniak, V.; and Hui, D., 2019, “Fatigue Behavior of Concrete Beams Prestressed with Partially Bonded CFRP Bars Subjected to Cyclic Loads,” Materials (Basel), V. 12, No. 20, Oct., p. 3352. doi: 10.3390/ma12203352
Lee, C.; Shin, S.; and Lee, H., 2017, “Balanced Ratio of Concrete Beams Internally Prestressed with Unbonded CFRP Tendons,” International Journal of Concrete Structures and Materials, V. 11, No. 1, pp. 1-16. doi: 10.1007/s40069-016-0171-6
Lees, J. M., and Burgoyne, C. J., 1999, “Experimental Study of Influence of Bond on Flexural Behavior of Concrete Beams Pretensioned with Aramid Fiber Reinforced Plastics,” ACI Structural Journal, V. 96, No. 3, May-June, pp. 377-385.
Park, R., 1989, “Evaluation of Ductility of Structures and Structural Assemblages from Laboratory Testing,” Bulletin of the New Zealand National Society for Earthquake Engineering, V. 22, No. 3, pp. 155-166. doi: 10.5459/bnzsee.22.3.155-166
Peng, F., and Xue, W., 2018a, “Design Approach for Flexural Capacity of Concrete T-Beams with Bonded Prestressed and Nonprestressed FRP Reinforcements,” Composite Structures, V. 204, pp. 333-341. doi: 10.1016/j.compstruct.2018.07.091
Peng, F., and Xue, W., 2018b, “Analytical Approach for Flexural Capacity of FRP Prestressed Concrete T-Beams with Non-Prestressed Steel Bars,” Journal of Composites for Construction, ASCE, V. 22, No. 6, p. 04018063. doi: 10.1061/(ASCE)CC.1943-5614.0000903
Peng, F., and Xue, W., 2019a, “Reliability-Based Design Provisions for Flexural Strength of Fiber-Reinforced Polymer Prestressed Concrete Bridge Girders,” ACI Structural Journal, V. 116, No. 1, Jan., pp. 251-260. doi: 10.14359/51710876
Peng, F., and Xue, W., 2019b, “Calculating Method for Ultimate Tendon Stress in Internally Unbonded Prestressed Concrete Members,” ACI Structural Journal, V. 116, No. 5, Sept., pp. 225-234. doi: 10.14359/51716764
Peng, F.; Xue, W.; and Yu, T., 2023, “Cyclic Behavior of Polypropylene Fiber Reinforced Concrete Beams with Prestressed CFRP Tendons and Nonprestressed Steel Bars,” Engineering Structures, V. 275, Jan., p. 115201. doi: 10.1016/j.engstruct.2022.115201
Poudel, P.; Belarbi, A.; Gencturk, B.; and Dawood, M., 2022, “Flexural Behavior of Full-Scale, Carbon-Fiber-Reinforced Polymer Prestressed Concrete Beams,” PCI Journal, V. 67, No. 5, Sept.-Oct., pp. 22-39. doi: 10.15554/pcij67.5-01
Rizkalla, N. S., 2000, “Partial Bonding and Partial Prestressing Using Stainless Steel Reinforcement for Members Prestressed with FRP,” master’s dissertation, Queen’s University, Kingston, ON, Canada, 212 pp.
Safan, M. A., 2013, “Flexural Behavior and Design of Steel-GFRP Reinforced Concrete Beams,” ACI Materials Journal, V. 110, No. 6, Nov.-Dec., pp. 677-685.
Sharaky, I. A.; Torres, L.; and Sallam, H. E. M., 2015, “Experimental and Analytical Investigation into the Flexural Performance of RC Beams with Partially and Fully Bonded NSM FRP Bars/Strips,” Composite Structures, V. 122, pp. 113-126. doi: 10.1016/j.compstruct.2014.11.057
Sun, Y.; Wu, T.; Liu, X.; and Zhang, B., 2022, “Failure Mode and Flexural Capacity of Concrete Beams Prestressed with Unbonded FRP Tendons,” Composite Structures, V. 283, p. 114956. doi: 10.1016/j.compstruct.2021.114956
Xue, W.; Cheng, B.; Zheng, R.; Li, L.; and Li, J., 2011, “Seismic Performance of Nonprestressed and Prestressed HPC Frames under Low Reversed Cyclic Loading,” Journal of Structural Engineering, ASCE, V. 137, No. 11, pp. 1254-1262. doi: 10.1061/(ASCE)ST.1943-541X.0000367