Title:
Shear Behavior of Externally Prestressed Concrete Beams with Draped Tendons
Author(s):
Jia-Nan Qi, Jing-Quan Wang, Zhongguo John Ma, and Teng Tong
Publication:
Structural Journal
Volume:
113
Issue:
4
Appears on pages(s):
677-688
Keywords:
arch action; concrete beams; draped tendons; external prestressing; shear crack; shear strength; truss action; truss-arch model
DOI:
10.14359/51688746
Date:
7/1/2016
Abstract:
Nine T-beams, prestressed with external tendons, were tested to failure to investigate the effect of prestressing, shear span-depth ratio, shear reinforcement, and bend angle of external tendons on the shear behavior and ultimate capacity of externally prestressed concrete beams. Test results indicated that the application of straight tendons did not change the load-transfer path and the entire configuration of arch action. A new fan-shaped crack region was found beyond the shear span when draping external tendons, which was defined as the secondary fan-shaped crack region. Considering the effect of draped tendons by supplementing the secondary arch action for shear strength of externally prestressed concrete beams, a new truss arch model was proposed. The accuracy of the proposed model was verified by testing results, and compared with the shear strength predictions of ACI 318-11, AASHTO LRFD, and MC2010.
Related References:
1. Zwoyer, E. M., and Siess, C. P., “Ultimate Strength in Shear of Simply-Supported Prestressed Concrete Beams without Web Reinforcement,” ACI Journal Proceedings, V. 51, No. 2, Feb. 1954, pp. 181-200.
2. Ng, S. T. K., and Soudki K., “Shear Behavior of Externally Prestressed Beams with Carbon Fiber-Reinforced Polymer Tendons,” ACI Structural Journal, V. 107, No. 4, July.-Aug. 2010, pp. 443-450.
3. Joint ASCE-ACI Committee 445, “Recent Approaches to Shear Design of Structural Concrete,” Journal of Structural Engineering, ASCE, V. 124, No. 12, 1998, pp. 1375-1417. doi: 10.1061/(ASCE)0733-9445(1998)124:12(1375)
4. Reineck, K. H.; Kuchma, D. A.; Kim, K. S.; and Marx, S., “Shear Database for Reinforced Concrete Members without Shear Reinforcement,” ACI Structural Journal, V. 100, No. 2, Mar.-Apr. 2003, pp. 240-249 and Appendix B.
5. Collins, M. P.; Bentz, E. C.; and Sherwood, E. G., “Where is Shear Reinforcement Required? Review of Research Results and Design Procedures,” ACI Structural Journal, V. 105, No. 5, Sept.-Oct. 2008, pp. 590-600 and Appendix A.
6. Xie, L. P.; Bentz, E. C.; and Collins, M. P., “Influence of Axial Stress on Shear Response of Reinforced Concrete Elements,” ACI Structural Journal, V. 108, No. 6, Nov.-Dec. 2011, pp. 745-754.
7. Wang, J. Q.; Qi, J.; and Zhang, J., “Optimization Method and Experimental Study on the Shear Strength of Externally Prestressed Concrete Beams,” Advances in Structural Engineering, V. 17, No. 4, 2014, pp. 607-615. doi: 10.1260/1369-4332.17.4.607
8. Ma, Z. J.; Tadros, M. K.; and Baishya, M., “Shear Behavior of Pretensioned High Strength Concrete Bridge I-Girders,” ACI Structural Journal, V. 97, No. 1, Jan.-Feb. 2000, pp. 185-192.
9. Foure, B.; Hoang, L. H.; Bouafia, Y.; Soubret, R.; and Belaloui, F., “Shear Strength of Externally Prestressed Beams,” External Prestressing in Structures, 1993, pp. 309-319.
10. Kondo, E.; Mutsuyoshi, H.; Takahashi, H.; and Sano, M., “Influence of External Prestressing Force on Shear Strength of PC Beams,” Transactions of the Japan Concrete Institute, V. 16, 1994, pp. 395-402.
11. Tan, K. H., and Ng, C. K., “Effect of Shear in Externally Prestressed Beams,” ACI Structural Journal, V. 95, No. 2, Mar.-Apr. 1998, pp. 116-127.
12. Tan, K. H., and Naaman, A. E., “Strut-and-Tie Model for Externally Prestressed Concrete Beams,” ACI Structural Journal, V. 90, No. 6, Nov.-Dec. 1993, pp. 683-691.
13. Tan, K. H., and Tjandra, R. A., “Shear Deficiency in Reinforced Concrete Continuous Beams Strengthened with External Tendons,” ACI Structural Journal, V. 100, No. 5, Sept.-Oct. 2003, pp. 565-572.
14. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-11) and Commentary,” American Concrete Institute, Farmington Hills, MI, 2011, 503 pp.
15. AASHTO-LRFD, “Bridge Design Specifications,” American Association of State Highway and Transportation Officials, Washington, DC, 2012, 1661 pp.
16. CEB-FIP Bulletin d’Information, “Model Code MC2010 Final Draft,” International Federation for Structural Concrete (fib), Lausanne, Switzerland, 2012, 370 pp.
17. MacGregor, J. G.; Sozen, M. A.; and Siess, C. P., “Effect of Draped Reinforcement on Behavior of Prestressed Concrete Beams,” ACI Journal Proceedings, V. 57, No. 6, June 1960, pp. 649-677.
18. MacGregor, J. G., and Bartlett, F. M., Reinforced Concrete-Mechanics and Design, Prentice Hall Canada Inc., Scarborough, ON, Canada, 2000, 1041 pp.
19. Kim, D.; Kim, W.; and White, R. N., “Prediction of Reinforcement Tension Produced by Arch Action in RC Beams,” Journal of Structural Engineering, ASCE, V. 124, No. 6, 1998, pp. 611-622. doi: 10.1061/(ASCE)0733-9445(1998)124:6(611)
20. Kim, B. H., and Yun, Y. M., “An Indeterminate Strut-Tie Model and Load Distribution Ratio for RC Deep Beams—(I) Model & Load Distribution Ratio,” Advances in Structural Engineering, V. 14, No. 6, 2011, pp. 1031-1041. doi: 10.1260/1369-4332.14.6.1031
21. Pan, Z. F., and Li, B., “Truss-Arch Model for Shear Strength of Shear-Critical Reinforced Concrete Columns,” Journal of Structural Engineering, ASCE, V. 139, No. 4, 2013, pp. 548-560. doi: 10.1061/(ASCE)ST.1943-541X.0000677
22. He, Z. Q.; Liu, Z.; and Ma, Z. J., “Investigation of Load-Transfer Mechanisms in Deep Beams and Corbels,” ACI Structural Journal, V. 109, No. 4, July-Aug. 2012, pp. 467-476.
23. Vecchio, F. J., and Collins, M. P., “The Modified Compression-Field Theory for Reinforced Concrete Elements Subjected to Shear,” ACI Journal Proceedings, V. 83, No. 2, Mar.-Apr. 1986, pp. 219-231.
24. Bentz, E. C.; Vecchio, F. J.; and Collins, M. P., “Simplified Modified Compression Field Theory for Calculating Shear Strength of Reinforced Concrete Elements,” ACI Structural Journal, V. 103, No. 4, July-Aug. 2006, pp. 614-624.
25. Foster, S. J., and Gilbert, R. I., “The Design of Nonflexural Members with Normal and High-Strength Concretes,” ACI Structural Journal, V. 93, No. 1, Jan.-Feb. 1996, pp. 3-10.