Title:
Seismic Performance Assessment of L-Shaped Reinforced Concrete Columns
Author(s):
Thanh Phuong Pham and Bing Li
Publication:
Structural Journal
Volume:
112
Issue:
6
Appears on pages(s):
667-678
Keywords:
L-shaped columns; reinforced concrete; seismic; shear strength
DOI:
10.14359/51688053
Date:
11/1/2015
Abstract:
This paper presents an experimental investigation carried out
on 10 reinforced concrete (RC) columns with L-shaped sections
subjected to simulated seismic loadings. The primary objective
of the study was to assess the suitability of using L-shaped RC
columns in regions of low-to-moderate seismic risk. The variables of interest included the axial load, loading direction, and aspect ratio. The specimen performances were analyzed and discussed in terms of crack patterns, hysteretic response, curvature distribution, displacement decomposition, strain profile, and energy dissipation capacity. Results highlighted that the L-shaped columns possessed good seismic resistance, that failure mechanism of L-shaped columns was mainly governed by vertical splitting cracks, and that shear strength of L-shaped columns was not significantly affected by the level of applied axial force and the direction of horizontal force while initial stiffness was considerably affected by aspect ratio. Further analysis showed that ignoring the contribution of flanges, the shear equation (special provisions for walls) in ACI 318-11 yields good estimations of shear strength for the cases of L-shaped columns.
Related References:
1. Marin, J., “Design Aids for L-Shaped Reinforced Concrete Columns,” ACI Journal Proceedings, V. 76, No. 11, Nov. 1979, pp. 1197-1216.
2. Ramamurthy, L. N., and Khan, T. A. H., “L-Shaped Column Design for Biaxial Eccentricity,” Journal of Structural Engineering, ASCE, V. 109, No. 8, 1983, pp. 1903-1917. doi: 10.1061/(ASCE)0733-9445(1983)109:8(1903)
3. Hsu, C.-T. T., “Biaxial Loaded L-Shaped Reinforced Concrete Columns,” Journal of Structural Engineering, ASCE, V. 111, No. 12, 1985, pp. 2576-2595. doi: 10.1061/(ASCE)0733-9445(1985)111:12(2576)
4. Tran, C. T. N., and Li, B., “Initial Stiffness of Reinforced Concrete Columns with Moderate Aspect Ratios,” Advances in Structural Engineering, V. 15, No. 2, 2012, pp. 265-276. doi: 10.1260/1369-4332.15.2.265
5. Pham, T. P., and Li, B., “Seismic Behavior of RC Columns under Different Loading Directions,” ACI Structural Journal, V. 110, No. 5, Sept.-Oct. 2013, pp. 833-843.
6. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-11) and Commentary,” American Concrete Institute, Farmington Hills, MI, 2011, 503 pp.
7. Pham, T. P., and Li, B., “Seismic Performance of Reinforced Concrete Columns with Plain Longitudinal Reinforcing Bars,” ACI Structural Journal, V. 111, No. 3, May-June 2014, pp. 561-572. doi: 10.14359/51686572
8. Pham, T. P., and Li, B., “Splitting Failure of Reinforced Concrete Columns,” Journal of Structural Engineering, ASCE, V. 140, No. 3, 2014, doi: 10.1061/(ASCE)ST.1943-541X.0000859
9. Priestley, M. J. N., and Kowalsky, M. J., “Aspects of Drift and Ductility Capacity of Rectangular Cantilever Structural Walls,” Bulletin of the New Zealand National Society for Earthquake Engineering, V. 31, No. 2, 1998, pp. 73-85.
10. ASCE/SEI 43-05, “Seismic Design Criteria for Structures, Systems, and Components in Nuclear Facilities,” American Society of Civil Engineers, Reston, VA, 2005, 98 pp.