Title:
SP-339-13: Seismic Performance of Full-Scale Reinforced Concrete Beam-Column Connections Extracted From Earthquake-Damaged Buildings
Author(s):
Giulio Leon Flores, Reza V. Farahani, Hussien Abdel Baky, and Paul C. Rizzo
Publication:
Symposium Paper
Volume:
339
Issue:
Appears on pages(s):
217-238
Keywords:
seismic performance, full-scale seismic test, measured lateral stiffness, beam-column connections, precast concrete frames
DOI:
10.14359/51724704
Date:
3/1/2020
Abstract:
This paper presents the structural testing of four full-scale reinforced concrete beam-column connections, extracted from reinforced concrete buildings that suffered minor damage from the Canterbury Earthquakes in New Zealand. Two connections are extracted from a moment frame comprising the secondary seismic-resisting system of a concrete building; two are extracted from moment frames of the primary seismic-resisting systems of a precast concrete building. The seismic performance of the connections is evaluated from the test results and compared to recommendations in ASCE 41 (2013) for the evaluation of existing buildings. Due to the size of the specimens, the tests were stopped when the actuator reached its maximum stroke, at interstory drifts between 2.5% and 3. The cast-in-place connections showed moderate damage after the tests, at ductility levels above 2.9, and their initial lateral stiffness was approximately 80% of the lateral stiffness of numerical models representing the undamaged state. The precast connections exhibited extensive damage along the construction joint between the precast beams and the cast-in-place beam-column joint, at ductility levels above 3.4. The plastic mechanism was governed by sliding shear of the precast beams, which caused severe stiffness deterioration at the end of the tests. The measured stiffness in this case was approximately half of the stiffness predicted by numerical models in which nonlinearity is considered in the form of flexural plastic hinges only. This unexpected behavior is attributed to the low quantity of reinforcing steel crossing the construction joint, and presumably earthquake damage.
Related References:
ACI Committee 318, 2008. “Building Code Requirements for Structural Concrete (ACI 318-08) and Commentary.” American Concrete Institute, Farmington Hills, Michigan.
ACI Committee 374, 2005. “Acceptance criteria for moment frames based on structural testing (ACI 374.1-05) and Commentary.” American Concrete Institute, Farmington Hills, Michigan.
ACI-ASCE Joint Committee 352, 2005. “Recommendations for design of beam-column connections in monolithic reinforced concrete structures.” American Concrete Institute, Farmington Hills, Michigan.
ASCE/SEI 41, 2013. “Seismic evaluation and retrofit of existing buildings.” American Society of Civil Engineers. Reston, Virginia.
NZS 3101, 2006, “Concrete Structures Standard.” Standards New Zealand, Wellington, New Zealand.
Birely, A., Lowes, L., Lehman, D. (2009). “A practical model for beam-column connection behavior in reinforced concrete frames”, Proc., ATC & SEI Conference on Improving the Seismic Performance of Existing Buildings and Other Structures, ASCE.
Bull, D., “Guidelines for the Use of Structural Precast Concrete in Buildings: Report of a Study Group of the New Zealand Concrete Society and the New Zealand National Society for Earthquake Engineering.” Centre for Advanced Engineering, Christchurch, New Zealand, 1999, 154 pp.
Computers and Structures Inc., 2008. “Technical Note Material Stress-Strain Curves.” Berkeley, California.
Computers and Structures Inc., 2013. “CSI Analysis Reference Manual for SAP2000®,” ISO# GEN062708M1, Rev.10, Berkeley, California.
Leon, G., Rizzo, P., Farahani, R., Abdel Baky, H., 2017, “Seismic assessment of a reinforced concrete frame beam-column connection extracted from an earthquake-damaged building,” submitted for publication, Proc., ASCE/SEI Structures Congress, Denver, Co.
Park, R., 1989. “Evaluation of Ductility of Structures and Structural Assemblages from Laboratory Testing.”
Bulletin Of The New Zealand National Society For Earthquake Engineering, V. 22, No. 3, pp. 155-166.
Park, R., 1995. “A Perspective on the Seismic Design of Precast Concrete Structures.” PCI Journal, V. 40, No. 3, pp. 40-60.
Park, R., Paulay, T., 1975, “Reinforced concrete structures.” John Wiley & Sons, Inc.
Paulay, T., Priestley, M.J.N., 1992. “Seismic Design of Reinforced Concrete and Masonry Buildings.” John Wiley & Sons, Inc.
Restrepo, J., Park, R., Buchanan, A., 1995. “Test on connections of earthquake resisting precast reinforced concrete perimeter frames of buildings.” PCI Journal, V. 40, No. 4, pp. 44-61.