Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete
Abstract
:1. Introduction
1.1. Bond Strength
1.2. Top-Bar Effect
2. Experimental Program
2.1. Mixture Proportioning and Workability Characteristics
Type | Wall No. | Mix Proportions | Descriptions |
---|---|---|---|
SCC | 1 | 34-440-HE20%FA-S/A54-VMA | Highly viscous to simulate lack of consolidation |
Plastic viscosity = 300 Pa.s | |||
Maximum settlement = 0.44% | |||
2 | 40-500-MS-S/A46-VMA * | Low viscosity, | |
Plastic viscosity = 20 Pa.s | |||
Maximum settlement = 0.59% | |||
3 | 40-440-MS-S/A54-VMA | Unstable mixture, | |
Plastic viscosity = 70 Pa.s | |||
Maximum settlement = 0.62% | |||
4 | 34-500-HE20%FA-S/A46-VMA ** | Stable mixture, | |
Plastic viscosity = 80 Pa.s | |||
Maximum settlement = 0.43% | |||
5 | 34-440-HE20%FA-S/A46 | Stable mixture, | |
Plastic viscosity = 150 Pa.s | |||
Maximum settlement = 0.3% | |||
HPC | 6 | 34-MS | Stable mixture, |
Plastic viscosity = 110 Pa.s | |||
Maximum settlement = 0.29% |
Wall No. | SCC 1 | SCC 2 | SCC 3 | SCC 4 | SCC 5 | HPC 6 |
---|---|---|---|---|---|---|
Cement, kg/m3 | Type HE | Type MS | Type MS | Type HE | Type HE | Type MS |
352 | 500 | 440 | 400 | 352 | 470 | |
HRWRA * demand, L/100 kg CM ** | 3.35 | 0.60 | 1.00 | 2.00 | 3.00 | 0.50 |
VMA dosage, L/100 kg CM | 0.1 | 0.1 | 0.1 | 0.1 | 0 | 0 |
Class F fly ash, kg/m3 | 88 | 0 | 0 | 100 | 88 | 0 |
Water, kg/m3 | 139 | 196 | 172 | 161 | 139 | 160 |
w/cm | 0.34 | 0.40 | 0.40 | 0.34 | 0.34 | 0.34 |
Sand, kg/m3 | 984 | 762 | 955 | 789 | 839 | 741 |
Coarse aggregate, kg/m3 | 838 | 894 | 814 | 927 | 985 | 1050 |
Sand/total aggregate, by volume | 0.54 | 0.46 | 0.54 | 0.46 | 0.46 | 0.41 |
Slump flow, mm | 665 | 695 | 670 | 660 | 660 | 145 *** |
T-50 mm, s | 6.8 | 1.5 | 1.8 | 2.9 | 5.5 | – |
Visual stability index | 0.5 | 1 | 1 | 0.5 | 0.5 | 0 |
Air content, % | 2.4 | 2.3 | 1.9 | 2.0 | 1.1 | 2.7 |
Unit weight, kg/m³ | 2343 | 2352 | 2365 | 2360 | 2409 | 2429 |
Temperature, °C | 23 | 24 | 23 | 24.4 | 23.5 | 25 |
J-Ring, mm | 630 | 640 | 605 | 630 | 605 | – |
Filling capacity, % | 92 | 93 | 89 | 91 | 82 | – |
Maximum surface settlement, % | 0.44 | 0.59 | 0.62 | 0.43 | 0.30 | 0.29 |
Yield stress, Pa | 5 | 32 | 37 | 25 | 12 | 575 |
Plastic viscosity, Pa.s | 300 | 20 | 70 | 80 | 150 | 110 |
2.2. Bond Strength Measurement of Prestressing Strands
3. Results and Discussion
3.1. In-Place Compressive Strength
Mix. No | Distance from Bottom, mm | Compressive Strength, MPa | f'c core/f'c cylinder (%) | ||||
---|---|---|---|---|---|---|---|
1 | 2 | 3 | Mean | C.O.V. * (%) | |||
Wall No. 1 | 120 | 81.9 | 77.9 | 78.3 | 79.4 | 2.79 | 98 |
550 | 71.0 | 77.1 | 75.1 | 74.4 | 4.16 | 92 | |
980 | 73.8 | 74.4 | 74.4 | 74.2 | 0.49 | 92 | |
1420 | 75.1 | 63.1 | 76.5 | 71.5 | 10.27 | 88 | |
Cylinder | 81.3 | 80.7 | 80.6 | 80.9 | 0.48 | 100 | |
Wall No. 2 | 120 | 55.9 | 55.0 | 50.7 | 53.9 | 5.21 | 99 |
550 | 48.1 | 45.4 | 47.3 | 46.9 | 2.87 | 86 | |
980 | 44.6 | 45.9 | 47.8 | 46.1 | 3.40 | 84 | |
1420 | 43.3 | 45.9 | 45.5 | 44.9 | 3.23 | 82 | |
Cylinder | 54.1 | 53.8 | 55.7 | 54.6 | 1.86 | 100 | |
Wall No. 3 | 120 | 60.4 | 59.0 | 58.8 | 59.4 | 1.44 | 98 |
550 | 55.7 | 54.4 | 55.1 | 55.1 | 1.19 | 91 | |
980 | 52.9 | 54.0 | 56.6 | 54.5 | 3.54 | 90 | |
1420 | 51.4 | 51.4 | 51.7 | 51.5 | 0.25 | 85 | |
Cylinder | 60.8 | 59.7 | 60.5 | 60.3 | 0.90 | 100 | |
Wall No. 4 | 120 | 71.0 | 70.0 | 73.8 | 71.6 | 2.76 | 95 |
550 | 70.9 | 68.9 | 71.0 | 70.3 | 1.71 | 93 | |
980 | 74.4 | 66.4 | 72.6 | 71.1 | 5.90 | 94 | |
1420 | 72.2 | 69.8 | 69.7 | 70.6 | 1.97 | 94 | |
Cylinder | 76.8 | 78.3 | 71.3 | 75.5 | 4.86 | 100 | |
Wall No. 5 | 120 | 75.2 | 69.6 | 68.1 | 71.0 | 5.34 | 91 |
550 | 74.2 | 72.1 | 69.1 | 71.8 | 3.60 | 92 | |
980 | 77.8 | 80.9 | 72.1 | 77.0 | 5.75 | 99 | |
1420 | 74.3 | 74.8 | 76.2 | 75.1 | 1.33 | 96 | |
Cylinder | 78.9 | 78.0 | 76.8 | 77.9 | 1.37 | 100 | |
Wall No. 6 | 120 | 64.8 | 63.9 | 66.0 | 64.9 | 1.66 | 99 |
550 | 64.7 | 61.7 | 59.0 | 61.8 | 4.59 | 94 | |
980 | 62.0 | 61.2 | 61.2 | 61.5 | 0.70 | 94 | |
1420 | 62.0 | 58.3 | 62.5 | 60.9 | 3.79 | 93 | |
Cylinder | 64.4 | 64.5 | 68.3 | 65.7 | 3.36 | 100 |
3.2. Pull-Out Bond Strength and Modification Factor (Top-Bar Factor)
Mix. No | Distance From Bottom, mm | Average Bond Strength, MPa | Normalized Bond Strength, MPa1/2 | Normalized Top-Bar Effect | |
---|---|---|---|---|---|
P3 level | UP3 | P3 level | |||
Wall No. 1 | 120 | 5.5 | 0.62 | 1.00 | |
550 | 3.3 | 0.37 | 1.61 | ||
980 | 3.1 | 0.36 | 1.75 | ||
1420 | 2.8 | 0.33 | 1.85 | ||
Wall No. 2 | 120 | 4.7 | 0.64 | 1.00 | |
550 | 4.1 | 0.60 | 1.05 | ||
980 | 2.7 | 0.40 | 1.57 | ||
1420 | 2.7 | 0.40 | 1.57 | ||
Wall No. 3 | 120 | 5.7 | 0.74 | 1.00 | |
550 | 5.4 | 0.73 | 1.02 | ||
980 | 4.0 | 0.54 | 1.37 | ||
1420 | 2.8 | 0.39 | 1.88 | ||
Wall No. 4 | 120 | 5.3 | 0.63 | 1.00 | |
550 | 5.5 | 0.66 | 0.96 | ||
980 | 5.6 | 0.66 | 0.95 | ||
1420 | 5.3 | 0.63 | 1.00 | ||
Wall No. 5 | 120 | 7.3 | 0.87 | 1.00 | |
550 | 7.4 | 0.87 | 1.00 | ||
980 | 7.0 | 0.80 | 1.10 | ||
1420 | 7.3 | 0.84 | 1.03 | ||
Wall No. 6 | 120 | 8.7 | 1.08 | 1.00 | |
550 | 8.3 | 1.06 | 1.02 | ||
980 | 7.1 | 0.91 | 1.19 | ||
1420 | 6.2 | 0.79 | 1.36 |
3.3. Effect of Stability on Homogeneity of In-Place Compressive and Bond Strength
4. Conclusions
- Wall elements cast with stable mixtures exhibited more homogenous in-place compressive strengths and pull-out bond strengths compared with walls cast with unstable mixtures. On average, relative in-place compressive strength was about 90% of values obtained with the control cylinders.
- Walls cast with stable SCC and HPC exhibited lower modification factor between 1 and 1.36, whilst those cast with unstable mixtures exhibited a modification factor between 1.57 and 1.88. Despite the high fluidity of SCC, stable concrete can lead to more homogenous in-situ properties than HPC of normal consistency subjected to mechanical vibration.
- The recommendations to ensure homogenous in-situ properties are as follows: the concrete should have maximum surface settlement lower than 0.5%; plastic viscosity up to 160 Pa.s; relative compressive strength ratio (core to cylinder) higher than 90%; and top-bar effect lower or equal to 1.4. It is important to note that the selection of more viscous mixtures needs extra care to ensure an acceptable consolidation of the concrete. The lack of consolidation can lead to low bond stress between concrete and prestressing strand.
Acknowledgments
Author Contributions
Conflicts of Interest
References
- Self-Consolidating Concrete; ACI 237R-07; American Concrete Institute: Farmington Hills, MI, USA, 2007.
- Interim Guidelines for the Use of Self-Consolidating Concrete in Precast/Prestressed Concrete Institute Member Plants; TR-6-03; Precast/Prestressed Concrete Institute: Chicago, IL, USA, 2003.
- The European Guidelines for Self-Compacting Concrete; European Federation of National Trade Associations (EFNARC): London, UK, 2005.
- Nehdi, M.L. Only tall things cast shadows: Opportunities, challenges and research needs of self-consolidating concrete in super-tall buildings. Constr. Build. Mater. 2013, 48, 80–90. [Google Scholar] [CrossRef]
- Juvas, K. The European experience of working with self-compacting concrete in the precast concrete industry. In Proceedings of the Combining the Second North American Conference on the Design and Use of Self-Consolidating Concrete and the Fourth International RILEM Symposium on Self-Compacting Concrete, Chicago, IL, USA, 30 October–2 November 2005; pp. 1105–1111.
- Juvas, K. Experiences of working with self-compacting concrete in the precast industry. In Proceedings of the 5th International RILEM Symposium on Self-Compacting Concrete, Ghent, Belgium, 3–5 September 2007; pp. 933–938.
- Camacho, R.E.R.; Afif, R.U.; Corona, G.M.; Roman, H.M.; Sanchez, M. Applications of SCC technology for precast/prestressed elements: The mexican experiences. In Proceedings of the 5th International RILEM Symposium on Self-Compacting Concrete, Ghent, Belgium, 3–5 September 2007; pp. 1071–1078.
- Ouchi, M.; Nakamura, S.; Osterson, T.; Hallberg, S.; Lwin, M. Applications of Self-Compacting Concrete in Japan, Europe and the United States; RILEM Publications SARL: Bagneux, France, 2003; pp. 1–20. [Google Scholar]
- Domone, P.L. Self-compacting concrete: An analysis of 11 years of case studies. Cem. Concr. Compos. 2006, 28, 197–208. [Google Scholar] [CrossRef]
- Moustafa, S. Pull-out strength of strand and lifting loops. Concr. Technol. Assoc. Tech. Bull. 1974, 74-B5, 20. [Google Scholar]
- Logan, D.R. Acceptance criteria for bond quality of strand for pretensioned prestressed concrete applications. PCI J. 1997, 42, 52–90. [Google Scholar] [CrossRef]
- Long, W.J.; Khayat, K.H.; Lemieux, G.; Hwang, S.D.; Han, N.X. Performance-based specifications of workability characteristics of prestressed, precast self-consolidating concrete—A North American prospective. Materials 2014, 7, 2474–2489. [Google Scholar] [CrossRef]
- Holschemacher, K.; Klug, Y. A Database for the Evaluation of Hardened Properties of SCC; Leipzig Annual Civil Engineering Report No. 7; Universität Leipzig: Leipzig, Germany, 2002; pp. 123–134. [Google Scholar]
- Koning, G.; Holschemacher, K.; Dehn, F.; Weibe, D. Self-compacting concrete-time development of materials properties and bond behavior. In Proceedings of 2nd International Symposium on Self-Compacting Concrete, Tokyo, Japan, 23–25 October 2001; pp. 507–516.
- Chan, Y.W.; Chen, Y.S.; Liu, Y.S. Development of bond strength of reinforcement steel in SCC. ACI Mater. J. 2003, 100, 490–498. [Google Scholar]
- Khayat, K.H.; Manai, K.; Trudel, A. In-situ mechanical properties of wall elements cast using self-consolidating concrete. ACI Mater. J. 1997, 94, 491–500. [Google Scholar]
- Assaad, J.; Khayat, K.H.; Daczko, J. Evaluation of static stability of self-consolidating concrete. ACI Mater. J. 2004, 101, 207–215. [Google Scholar]
- Gibbs, J.C.; Zhu, W. Strength of hardened self-compacting concrete. In Proceedings of the 1st RILEM International Symposium on SCC, Stockholm, Sweden, 9–12 September 1999; pp. 199–209.
- Sonebi, M.; Bartos, P.J.M. Hardened SCC and its bond with reinforcement. In Proceedings of the 1st RILEM International Symposium on Self-Compacting Concrete, Stockholm, Sweden, 9–12 September 1999; pp. 275–289.
- Sonebi, M.; Rooney, M.; Bartos, P. In-situ compressive strength of self-compacting concrete. Concrete 2002, 36, 48–49. [Google Scholar]
- Castel, A.; Vidal, T.; Francois, R. Bond and cracking properties of self-consolidating concrete. Constr. Build. Mater. 2010, 24, 1222–1231. [Google Scholar] [CrossRef]
- Castel, A.; Vidal, T.; Viriyametanont, K.; Francois, R. Effect of reinforcing bar orientation and location on bond with self-compacting concrete. ACI Struct. J. 2006, 103, 559–567. [Google Scholar]
- Hegger, J.; Gortz, S.G.; Kommer, B.; Tiggs, C.; Dross, C. Prestressed precast beams made of self-compacting concrete. Betonwerk + Fertigteil-Technik (Concrete Plant + Precast Technology) 2003, 8, 40–46. [Google Scholar]
- Martí-Vargas, J.R.; Serna-Ros, P.; Arbeláez, C.A.; Rigueira-Victor, J.W. Transfer and anchorage bond behaviour in self-compacting concrete. Mater. Constr. 2006, 56, 27–42. [Google Scholar]
- Hwang, S.D.; Khayat, K.H. Comparison of in situ properties of wall elements cast using self-consolidating concrete. Mater. Struct. 2012, 45, 123–141. [Google Scholar] [CrossRef]
- Attiogbe, E.K.; See, H.T.; Daczko, J.A. Engineering properties of self-consolidating concrete. In Proceedings of the 1st North American Conference on the Design and Use of SCC, Chicago, IL, USA, 9–12 November 2002; pp. 371–376.
- Khayat, K.H.; Petrov, N.; Attiogbe, E.; See, H. Uniformity of bond strength of prestressing strands in conventional flowable and self-consolidating concrete mixtures. In Proceedings of the 3rd International Symposium on Self-Compacting Concrete, Reykjavik, Iceland, 17–20 August 2003; pp. 703–712.
- Valcuende, M.; Parra, C. Bond behaviour of reinforcement in self-compacting concretes. Constr. Build. Mater. 2009, 23, 162–170. [Google Scholar] [CrossRef]
- Schiessl, A.; Zilch, K. The Effect of the modified composition of SCC on shear and bond behavior. In Proceedings of the 2nd International Symposium on Self-Compacting Concrete, Tokyo, Japan, 23–25 October 2001; pp. 501–506.
- Long, W.J.; Lemieux, G.; Hwang, S.D.; Khayat, K.H. Statistical models to predict fresh and hardened properties of self-consolidating concrete. Mater. Struct. 2012, 45, 1035–1052. [Google Scholar] [CrossRef]
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Long, W.-J.; Khayat, K.H.; Lemieux, G.; Hwang, S.-D.; Xing, F. Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete. Materials 2014, 7, 6930-6946. https://doi.org/10.3390/ma7106930
Long W-J, Khayat KH, Lemieux G, Hwang S-D, Xing F. Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete. Materials. 2014; 7(10):6930-6946. https://doi.org/10.3390/ma7106930
Chicago/Turabian StyleLong, Wu-Jian, Kamal Henri Khayat, Guillaume Lemieux, Soo-Duck Hwang, and Feng Xing. 2014. "Pull-Out Strength and Bond Behavior of Prestressing Strands in Prestressed Self-Consolidating Concrete" Materials 7, no. 10: 6930-6946. https://doi.org/10.3390/ma7106930