Effect of the transverse reinforcement spacing in nodal zones on the seismic behavior factor of RC frames according to Algerian design code RPA99/version2003
Abstract
The seismic behavior of reinforced concrete (RC) frames is significantly influenced by the confinement provided by transverse reinforcement. This study investigates the effect of transverse reinforcement spacing on the seismic behavior factor (R) of regular RC frames. The objective is to determine which spacing provides an R value in accordance with the Algerian seismic design code (RPA99/version 2003). To evaluate this effect, nonlinear pushover analysis is performed for each configuration. The confined concrete properties are defined using Mander’s model, accounting for variations in compressive strength and strain capacity due to different stirrup spacings. The seismic behavior factor (R) is computed based on the overstrength factor (Rs) and the ductility factor (Rµ), derived from the capacity curves. The results of this study will provide insights into the influence of confinement on ductility and overstrength, allowing for the identification of an optimal stirrup spacing that ensures compliance with the RPA99/version 2003 seismic design code. The findings will help improve reinforcement detailing recommendations for enhanced seismic performance of RC frames.
References
Annan C.D., Youssef M.A., & EL Naggar M.H. (2009). Seismic Overstrength in Braced Frames of Modular Steel Buildings. Journal of Earthquake Engineering, 13, 1-21.
Applied Technology Council, ATC-19 (1995). Structural Response Modification Factors. Redwood City, California.
Applied Technology Council, ATC-40 (1996). Seismic Evaluation and Retrofit of Concrete Buildings. Volume 1, Redwood City, California.
BAEL 91 (1992). Règles Techniques de Conception et de Calcul des Ouvrages et Constructions en Béton Armé suivant la Méthode des Etats Limites. Edition Eyrolles
Bruneau M., Uang C.M., & Whittaker A. (1998). Ductile Design of Steel Structures. McGraw- Hill, New York, 381-409.
Chang, H.-J., Cho, J.-H., Kim, M.-G., & Kim, J.-H. (2025).Effects of Vertical Irregularity on Transverse Reinforcement Spacing in Reinforced Concrete Columns to Avoid Shear Failure Subjected to Seismic Behavior.Buildings , 15, 785.
Ciutina Liviu Adrian (2003). Assemblage et Comportement Sismique de Portiques en Acier et Mixtes Acier-Béton : Expérimentation et Simulation Numérique. Thèse de Doctorat, Institut National des Sciences Appliquées, Rennes, France
Fardis, M. N. (2009). Seismic Design, Assessment and Retrofitting of Concrete Buildings: Based on EN-Eurocode 8. Springer.
Federal Emergency Management Agency (FEMA) (1997). NEHRP the Seismic Rehabilitation of Buildings, Rep. FEMA 273 (Guidelines). Washington, D.C.
Intel M., & Ozmen H.B. (2006). Effect of Plastic Hinge Properties in Nonlinear Analysis of Reinforced Concrete Buildings. Engineering Structures, 28, 1494-1502
Krawinkler, H., & Nassar, A. A. (1992). Seismic Design Based on Ductility and Cumulative Damage Demand and Capacities. In Nonlinear Seismic Analysis and Design of Reinforced Concrete Buildings, P. Fajfar and H. Krawinkler, Eds., Elsevier Apllied Science, New York, USA.
Kyei, C., & Braimah, A. (2017). Effects of transverse reinforcement spacing on the response of reinforced concrete columns subjected to blast loading. Engineering Structure, 142, 148–164.
Louzai, A., & Abed, A. (2015). Evaluation of the seismic behavior factor of reinforced concrete frame structures based on comparative analysis between non-linear static pushover and incremental dynamic analyses. Bulletin of Earthquake Engineering, 13, 1773–1793.
Mander, J. B., Priestley, M. J. N., & Park, R. (1988). Theoretical Stress-Strain Model for Confined Concrete. Journal of Structural Engineering, ASCE, 114(8), 1804-1826.
Michael, D.S., Nasim, K.S., David, I.M., & William, F. C. (2003). Evaluation of Displacement-Based Methods and Computer Software for Seismic Analysis of Highway Bridges. Research Project T1804, Task7, Department of Civil and Environmental Engineering, Washington State University.
Mitchell D., & Paultre P. (1994). Ductility and Overstrength in Seismic Design of Reinforced Concrete Structures. Canadian Journal of Civil Engineering, Vol. 21, 1049-1060.
Moehle, J. P., & Mahin, S. A. (1991). Observations on the behavior of reinforced concrete buildings during earthquakes. Earthquake-Resistant Concrete Structures-Inelastic Response and Design, SP-127, S. K. Ghosh, ed., American Concrete Institute, Farmington Hills, Mich., 67-89.
Mwafy, A.M., & Elnashai A.S. (2001). Static Pushover versus Dynamic Collapse Analysis of RC Building. Engineering Structures, Vol. 23, pp. 407-424.
Mwafy, A.M., & Elnashai A.S. (2002). Calibration of Force Reduction Factors of RC Buildings. Journal of Earthquake Engineering, Vol. 6, No. 2, 239-273.
Newmark, N.M., & Hall, W.J. (1982). Earthquake Spectra and Design. EERI Monograph Series, EERI, Okland, CA, U.S.A.
Park, R., & Paulay, T. (1975). Reinforced Concrete Structures. Wiley.
Priestley, M. J. N., Seible, F., & Calvi, G. M. (1996). Seismic Design and Retrofit of Bridges. Wiley.
Rahgozar, M.A., & Humar, J.L. (1998). Accounting for Overstrength in Seismic Design of Steel Structures. Canadian Journal of Civil Engineering, Vol. 25, 1-15.
Règlement Parasismique Algérien RPA99/version2003 (2003). Centre National de Recherche Appliquée en Génie Parasismique.
Rozman, M., Fajfar, P. (2009). Seismic response of a RC frame building designed according to old and modern practices. Bulletin of Earthquake Engineering, 7, 779–799.
Saiidi, M., & Sozen, M.A. (1981). Simple Nonlinear Seismic Response of R/C Structures. Journal of Structural Division, ASCE, 107, 937-952.
SAP2000 (2009). Three Dimensional Static and Dynamic Finite Element Analysis and Design of Structures V14, Computers and Structures, Inc., Berkeley, California.
Uang, C.M. (1991). Establishing R (or Rw) and Cd Factors for Building Seismic Provisions. Journal of Structural Engineering, ASCE, Vol. 117, No. 1, 19-28.
UBC 97 (1997). International Conference of Building Officials, Whittier, California.
Ulutas, H. (2024). Investigation of the Causes of Soft-Storey and Weak-Storey Formations in Low-and Mid-Rise RC Buildings in Turkiye. Buildings, 14, 1308.
Copyright (c) 2025 Amar Louzai , Ahmed Abed
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work.
