Title:
Chord Rotation Capacity and Strength of Diagonally Reinforced Concrete Coupling Beams
Author(s):
A. Lepage, R. D. Lequesne, A. S. Weber-Kamin, S. Ameen, and M.-Y. Cheng
Publication:
Structural Journal
Volume:
120
Issue:
6
Appears on pages(s):
137-150
Keywords:
backbone curve; beam aspect ratio; confining reinforcement; database; deformation capacity; force-deformation envelope; hoop spacing; reinforcement grade; shear stress
DOI:
10.14359/51739092
Date:
11/1/2023
Abstract:
A database of results from 27 tests of diagonally reinforced
concrete coupling beams was analyzed to develop improved
force-deformation envelopes (backbone curves) for modeling and
analysis of coupling beams. The database, which was selected from
a larger set of 60 test results, comprises specimens that generally
satisfy ACI 318-19 requirements. The analyses show that the
chord rotation capacity of diagonally reinforced concrete coupling
beams compliant with ACI 318-19 is closely correlated with beam
clear span-to-overall depth ratio and, to a lesser extent, the ratio
of hoop spacing to diagonal bar diameter. A simple expression is
proposed for estimating beam chord rotation capacity. Coupling
beam strength was shown to be more accurately estimated from
flexural strength calculations at beam ends than other methods.
Recommendations are made for obtaining more accurate backbone
curves in terms of chord rotation capacity, strength, and stiffness.
Related References:
1. Paulay, T., and Binney, J. R., “Diagonally Reinforced Coupling Beams of Shear Walls,” Shear in Reinforced Concrete, SP-42, American Concrete Institute, Farmington Hills, MI, 1974, pp. 579-598.
2. Naish, D.; Fry, A.; Klemencic, R.; and Wallace, J., “Reinforced Concrete Coupling Beams—Part 1: Testing,” ACI Structural Journal, V. 110, No. 6, Nov.-Dec. 2013, pp. 1057-1066.
3. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-99) and Commentary (ACI 318R-99),” American Concrete Institute, Farmington Hills, MI, 1999, 369 pp.
4. ASCE/SEI 7-16, “Minimum Design Loads and Associated Criteria for Buildings and Other Structures,” American Society of Civil Engineers, Reston, VA, 2017, 822 pp.
5. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-19) and Commentary (ACI 318R-19) (Reapproved 2022),” American Concrete Institute, Farmington Hills, MI, 2019, 624 pp.
6. ASCE/SEI 41-17, “Seismic Evaluation and Retrofit of Existing Buildings,” American Society of Civil Engineers, Reston, VA, 2017, 576 pp.
7. ACI Committee 369, “Seismic Evaluation and Retrofit of Existing Concrete Buildings—Code and Commentary (ACI CODE-369.1-22),” American Concrete Institute, Farmington Hills, MI, 2022, 125 pp.
8. TBI, “Guidelines for Performance-Based Seismic Design of Tall Buildings (Tall Buildings Initiative),” Report No. 2017/06, Pacific Earthquake Engineering Research Center, University of California, Berkeley, Berkeley, CA, 2017, 145 pp.
9. Naish, D.; Fry, A.; Klemencic, R.; and Wallace, J., “Reinforced Concrete Coupling Beams—Part II: Modeling,” ACI Structural Journal, V. 110, No. 6, Nov.-Dec. 2013, pp. 1067-1076.
10. Cheng, M.-Y.; Gitomarsono, J.; and Zeng, H.-Y., “Cyclic Test of Diagonally Reinforced Concrete Coupling Beam with Different Shear Demand,” ACI Structural Journal, V. 116, No. 6, Nov. 2019, pp. 241-250. doi: 10.14359/51718010
11. Weber-Kamin, A. S.; Lequesne, R. D.; and Lepage, A., “Reinforced Concrete Coupling Beams with High-Strength Steel Bars,” SM Report No. 143, The University of Kansas Center for Research, Inc., Lawrence, KS, 2020, 598 pp.
12. Lequesne, R. D., “Behavior and Design of High-Performance Fiber-Reinforced Concrete Coupling Beams and Coupled-Wall Systems,” PhD dissertation, University of Michigan, Ann Arbor, MI, 2011, 277 pp.
13. Ameen, S.; Lequesne, R. D.; and Lepage, A., “Diagonally-Reinforced Concrete Coupling Beams with High-Strength Steel Bars,” SM Report No. 138, The University of Kansas Center for Research, Inc., Lawrence, KS, 2020, 346 pp.
14. Poudel, A.; Ameen, S.; Lequesne, R. D.; and Lepage, A., “Diagonally Reinforced Concrete Coupling Beams: Effects of Axial Restraint,” ACI Structural Journal, V. 118, No. 6, Nov. 2021, pp. 293-303.
15. Malcolm, R. C.; Bull, D. K.; Henry, R. S.; and Ingham, J. M., “The Effects of Axial Restraint in Reinforced Concrete Coupling Beams,” Proceedings of the New Zealand Concrete Industry Conference, Taupō, New Zealand, 2014, pp. 150-159.
16. Cheng, M.-Y.; Fikri, R.; and Chen, C.-C., “Experimental Study of Reinforced Concrete and Hybrid Coupled Shear Wall Systems,” Engineering Structures, V. 82, 2015, pp. 214-225. doi: 10.1016/j.engstruct.2014.10.039
17. Ameen, S.; Lequesne, R. D.; and Lepage, A., “Diagonally Reinforced Concrete Coupling Beams with Grade 120 (830) High-Strength Steel Bars,” ACI Structural Journal, V. 117, No. 6, Nov. 2020, pp. 199-210.
18. Weber-Kamin, A. S.; Ameen, S.; Lequesne, R. D.; and Lepage, A., “PRJ-3053 - Database of Diagonally-Reinforced Concrete Coupling Beams,” Designsafe-ci.org, 2021. doi: 10.17603/ds2-46wc-n185
19. Lepage, A.; Lequesne, R. D.; Weber-Kamin, A. S.; and Ameen, S., “Chord Rotation Capacity of Diagonally-Reinforced Concrete Coupling Beams,” 12th National Conference on Earthquake Engineering, Salt Lake City, UT, 2022, Paper No. 10806.
20. Lim, E.; Hwang, S.-J.; Cheng, C.-H.; and Lin, P.-Y., “Cyclic Tests of Reinforced Concrete Coupling Beam with Intermediate Span-Depth Ratio,” ACI Structural Journal, V. 113, No. 3, May-June 2016, pp. 515-524. doi: 10.14359/51688473
21. Lim, E.; Hwang, S.-J.; Wang, T.-W.; and Chang, Y.-H., “An Investigation on the Seismic Behavior of Deep Reinforced Concrete Coupling Beams,” ACI Structural Journal, V. 113, No. 2, Mar.-Apr. 2016, pp. 217-226.
22. Howard, B., “Seismic Response of Diagonally Reinforced Coupling Beams with Varied Hoop Spacings,” MS thesis, McGill University, Montreal, QC, Canada, 2017, 99 pp.
23. Kwan, A. K. H., and Zhao, Z.-Z., “Cyclic Behaviour of Deep Reinforced Concrete Coupling Beams,” Proceedings of the Institution of Civil Engineers - Structures and Buildings, V. 152, No. 3, 2002, pp. 283-293. doi: 10.1680/stbu.2002.152.3.283
24. Shimazaki, K., “De-Bonded Diagonally Reinforced Beam for Good Repairability,” Proceedings of the 13th World Conference on Earthquake Engineering, Vancouver, BC, Canada, 2004, Paper No. 3173.
25. Han, S. W.; Kang, J.-W.; Jee, H.-W.; Shin, M.; and Lee, K., “Cyclic Behavior of HPFRCC Coupling Beams with Bundled Diagonal Bars,” International Journal of Concrete Structures and Materials, V. 12, No. 1, 2018, Article No. 42. doi: 10.1186/s40069-018-0271-6
26. Han, S. W.; Lee, C. S.; Shin, M.; and Lee, K., “Cyclic Performance of Precast Coupling Beams with Bundled Diagonal Reinforcement,” Engineering Structures, V. 93, 2015, pp. 142-151. doi: 10.1016/j.engstruct.2015.03.034
27. Park, W.-S.; Kang, T. H.-K.; Kim, S.; and Yun, H.-D., “Seismic Performance of Moderately Short Concrete Coupling Beams with Various Reinforcements,” ACI Structural Journal, V. 117, No. 3, May 2020, pp. 141-154.
28. Gonzalez, E., “Seismic Response of Diagonally Reinforced Slender Coupling Beams,” MS thesis, The University of British Columbia, Vancouver, BC, Canada, 2001, 164 pp.