Effects of floor slabs on the flexural strength of beams in reinforced concrete buildings
The effects of floor slabs on the flexural strength of beams in reinforced concrete buildings under seismic action were verified through tests of frame assembly specimens. A series of experimental and analytical investigations were conducted from 2010 to 2014 in order to further validate the current design practices in Japan. Loading methods in the past beam component tests were reviewed with probable effects of floor slabs. A special loading set-up was used for the frame assembly specimens consisting of four columns and four beams with lengths of one span and two half spans in two directions. The four columns were loaded laterally and independently at mid-height of the upper storey and supported at mid-height of the lower storey with pin-fixed and pin-roller so that axial elongation of the beams and slab would not be constrained by the lateral forces. It has been found from these new loading tests that the tensile stresses in the floor slab reinforcing bars are generally uniform at the beam critical sections and up to the full slab width for the flexural strength when the slab is subjected to tension bending around one percent storey drift, which is much wider than assumed in the current design evaluation.
Architectural Institute of Japan (2009). “AIJ Standard for Structural Calculation of Reinforced Concrete Structures”. Article 8: Basics of Structural Analysis, AIJ, 63-64 (in Japanese).
Building Center of Japan (2007). “Guidelines for Structural Standard Requirements on Buildings”. BCJ, 620-663 (in Japanese).
Suzuki N, Otani S and Kobayashi Y (1984). “Three-Dimensional Beam-Column Subassemblages under Bidirectional Earthquake Loadings”. Proceedings of the 8th World Conference on Earthquake Engineering (8WCEE), San Francisco, Prentice-Hall, 6: 453-460.
Joglekar M et al. (1988). “Full Scale Tests of Beam-Column Joints” in US-Japan Research: Earthquake Effects on Reinforced Concrete Structures”. Special Publication SP-84, American Concrete Institute (ACI), USA, 271-304.
Zerbe HE and Durrani AJ (1985). “Effect of Slab on the Behavior of Exterior Beam to Column Connections”. Report No. 30, Department of Civil Engineering, Rice University, Houston, Texas.
French CW and Boroojerdi A (1989). “Contribution of RC Floor Slabs in Resisting Lateral Loads”. ASCE Journal of Structural Engineering, 115(1): 1-18. DOI: https://doi.org/10.1061/(ASCE)0733-9445(1989)115:1(1)
Qi X and Pantazopoulou SJ (1991). “Response of RC Frame under Lateral Loads”. ASCE Journal of Structural Engineering, 117(4): 1167-1188. DOI: https://doi.org/10.1061/(ASCE)0733-9445(1991)117:4(1167)
Kabeyasawa T, Shiohara H and Otani S (1984). “US - Japan Cooperative Research on RC Full-Scale Building Test, Part 5: Discussion on Dynamic Response System”. Proceedings of the 8th World Conference on Earthquake Engineering (8WCEE), San Francisco, Prentice-Hall, 6: 627-634.
Kabeyasawa Toshimi, Kabeyasawa Toshikazu, Matsumori T, Kabeyasawa Toshinori and Kim Y (2008). “Full-scale dynamic collapse tests of three-storey reinforced concrete buildings on flexible foundation at E-Defense”. Proceedings of the 14th World Conference on Earthquake Engineering (14WCEE), Beijing, China, S15-002:8pp.
Kabeyasawa Toshimi, Kabeyasawa Toshikazu, Matsumori T, Kim Y and Kabeyasawa Toshinori (2009). “Full-Scale 3-D Shake Table Tests on Reinforced Concrete Building Structures at E-Defense”. Proceedings of the 4th International Conference on Construction Materials (CONMAT09), August 24-26, Nagoya, 1-16.
Nagae T et al. (2010). “Test Results of Four-Storey Reinforced Concrete and Post-Tensioned Concrete Buildings, The 2010 E-Defense Shaking Table Test”. Proceedings of the 15th World Conference on Earthquake Engineering (15WCEE), Lisbon, Portugal, Paper No. 3870:10pp.
Dhakal RP, Peng BHH, Fenwick RC, Carr AJ and Bull DK (2014). “Cyclic Loading Test of a RC Frame with Precast-Prestressed Flooring System”. ACI Structural Journal, 111(4): 777-788. DOI: https://doi.org/10.14359/51686732
Kabeyasawa Toshikazu et al. (2011). “Static Loading Test of a Three-dimensional Frame Simulating High Rise Reinforced Concrete Building Structures Subjected to Many Cyclic Loads, Part 1 and Part 2”. Proceedings of AIJ Annual Meeting, 741-744.
Kabeyasawa Toshimi, Kabeyasawa Toshikazu, Xuan D and Fukuyama H (2015). “Frame Test on Effects of Slab to Beam Strength in Reinforced Concrete Buildings”. AIJ Journal of Structural Engineering, 61B: 103-110.
Copyright (c) 2017 Toshimi Kabeyasawa, Toshikazu Kabeyasawa, Hiroshi Fukuyama
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