ABSTRACT
Reinforced concrete (RC) buildings designed with non-ductile detailing may have serious structural deficiencies that lead to structural collapsed induced by earthquakes. These are commonly seen in old existing RC frame structures. Specifically, the failure observed in the beam-column joints follow with excessive column damage. This report evaluates the seismic performance of deficiencies in non-ductile RC columns and exterior RC beam-column joints, where the designs and details were taken directly from the old existing RC frame structure, Weiguan Jinlong, which collapsed in the Meinung earthquake in 2016. Structural deficiencies are represented by wider stirrups and crossties spacing for RC columns, and there are no joint transverse reinforcements.

An experimental investigation using cyclic testing was conducted for ½-scale two RC columns and ½-scale two RC beam-column joints. The dimensions of the specimen were designed to have two different cross-sectional column areas, 300 x 300 mm and 750 x 300 mm, with the same cross-sectional beam area of 400 x 250 mm.

The results indicated a poor response was exhibited in the case of both column specimens. The results were further proven by a comparison made with previous related studies, where lower energy dissipation and displacement ductility induced in stirrups and crossties resulted in spacing greater than 100 mm.

In the case of the RC beam-column joints, joint shear failure could be observed in the specimens. This was primarily attributed to the lack of joint shear reinforcement provided within the joint, which caused a reduction in the joint force capacity and a lack of the ductility necessary to overcome the earthquake force when it was induced into the system. The ductility was found to be less than desired (a value of 4) to survive an earthquake with a similar magnitude to that of El Centro. However, the specimen with a large column and small beam area exhibited much higher joint shear strength with less joint stress at the joint as compared to the specimen with a small column and a large beam area.

Further, triaxial shake table tests were carried out on a prototype of Weiguan Jinlong designed and built to a ½-scale, 3 story RC structure, to verify the performance of the RC columns at a structural level under real-life-type seismic loads. It was not possible to verify the performance of the RC beam-column joints in this research due to different number of beam frames in the joints. The behavior of the RC column specimens was observed to be slightly different in terms of crack patterns associated with real behavior in a triaxial test of a ½-scale, 3 story RC structure due to the different nature of the testing.

The performance levels of the RC columns and RC beam-columns were established, and comparisons were made to ASCE 41-13 default hinges currently implemented with the ETABS version 2016 software in the form of load and displacement curves. The RC columns were found to provide better simulation behavior than the RC beam-column joints. It is not possible to simulate an engineered FE model of a beam-column joint in the ETABS version 2016 software.

Keywords: Exterior beam-column joints, Columns; ½-scale 3 story RC structure; Quasi-static cyclic testing; Cracking; Hysterics curve; Ductility; Energy; Shear; Non-linear simulation; Plastic hinges

ACI318-14. (2014). Building Code Requirement for Structural Concrete (ACI 318-2014) and Commentary (318R-2014). Mich: American Concrete Institute, Farmington Hills.
ACI352R-02. (2002). Joint ACI-ASCE Committee 352: Recommendations for design of beam column joints in monolithic reinforced concrete structures. Farmington Hills, MI: American Concrete Inst (ACI).
Altoontash, A., & Lowes, L. N. (2003). Modeling Reinforced-Concrete Beam-Column Joints Subjected to Cyclic Loading . Structural Engineering @ ASCE, 1686-1697.
Alva, G. M., Ferreira, M. A., & El Debs, A. L. (2009). Partially Restrained Beam-Column Connection in Reinforced Concrete Structures. IBRACON Structures and Materials, 1983-4195.
Attaalla, S. A., & Agbabian, M. S. (2004). Perfomance of Interior Beam-Column Joints Cast from High Strength Concrete Under Seismic Loads. Advances in Structural Engineering, Volume 7 (2), 147-157.
Balaji, S., & Thirugnanam, G. S. (2017). Study on Exterior RC Beam-Column Joints Upgrade with SIFCON in Joint Core Under Reversed Cyclic Loading. Korean Society of Civil Engineers (KSCE) 21 (1).
Benavent-Climent, A. (2007). Seismic Behavior of RC Wide Beam-Column Connections Under Dynamic Loading. Journal of Earthquake Engineering, Volume 11, 493-511.
Beres, A., El-Borgi, S., White, R. N., & Gregely, P. (1992). Experimental Results of Repaired and Retrofitted Beam-Column Joint Tests in Lightly Reinforced Concrete Frame Buildings. New York: National Center for Earthquake Engineering Research.
Bindhu, K. R., Sukumar, P. m., & Jaya, K. P. (2009). Performance of Exterior Beam-Column Joints Under Seismic Type Loading. ISET Journal of Earthquake Technology, Volume 46 (2), 47-64.
Concrete, S. U. (2013). Code of Practice for Structural Use of Concrete. In B. D.-1. Center, Code of Practice for Structural Use of Concrete 2013. Mongkok, Kowloon: The GFovernment of the Hong Kong Special Administrative Region.
EASY.(2018,0517). Retrieved from http://www.ikpir.com/easy/html/ang/INDEX.HTM
Gencoglu, M., & Eren, I. (2002). An Experimental Study on the Effect of Steel Fiber Reinforced Concrete on the Behavior of the Exterior Beam-Column Joints Subjected to Reversal Cyclic Loading. Turkish J. Engineering Environment Science @ TUBITAK, 493-502.
Ghobarah, A., Aziz, T. S., & Biddah, A. (1996). Rehabilitation of Reinforced Concrete Beam-Column Joints. 11 World Conference on Earthquake Engineering, 1394.
Hakuto, S., Park, R., & Tanaka, H. (2000). Seismic load tests on interior and exterior beam-column joints with substandard reinforcing details. ACI Structural Journal, Vol. 97, No.1, 11-25.
Hsiao, F.-P. (2017). Introduction to Start-up Tests of 1/2-Scake RC Structures in NCREE Tainan Laboratory. NCREE Newsletter, Volume 12 (1), 3.
Huang, R. C., Kuang, J. S., & Behnam, H. (2017). Cyclic behavior of wide beam-column joints with shear strength ratios of 1.0 and 1.7. International Journal of Civil and Environmental Engineering; Vol: 11, No 4, 399-405.
Hwang S.J., and Lee, H.J. (1999). “Analytical Model for predicting shear strengths of exterior reinforced concrete beam-column joints for seismic resistance.” ACI Structural Journal, Vol. 96 No.6, 99 846-857
Kadarningsih , R., Satyarno, I., & Triwiyono, A. (2017). Analysis and design of reinforced concrete beam-column joint using King Cross steel profile. Yogyakarta, Indonesia: Elsevier Ltd.
Karayannis, C. G., Chalioris, C. E., & Sirkelis, G. M. (2008). Local retrofit of exteriro oRC beam-column joints using thin RC jackets - An experimental study. Earthquake Engineering and Structural Dynamics, 727-746.
Kasilingam, S., & Satavalekar, R. (2017). Experiments on ductile and non-ductile reinforced concrete frames under static and cyclic loading. Journal of Coupled Systems and Multiscale Dynamics, Volume 5 (1) , 38-49.
Koch, P. A. (1998). Seismic Response of High-Strength Concrete Beam-Column Slab Specimens. Montreal : National Library of Canada.
Kurama, Y., Sause, R., Pessiki, S., Wu, S., & Snyder, S. (1997). Seismic behavior, performance, and retrofit of non-ductile reinforced concrete frame structures. Earthquake Engineering Research Report 96-01, 67.
Kwan, A., & Ho, J. (2010). Ductility design of high-strength concrete beams and columns. Pokfulam: The University of Hong Kong.
Li, J., Pam, J. H., & Au, K. T. (2004). New Details of HSC Beam-Column Joints for Regions of Low to Moderate Seismicity . 13th World Conference on Earthquake Engineering (p. 449). Vancouver: 13 WCEE.
Liao, W.-C., Perceka, W., & Wang, M. (2017). Experiemental study of cyclic behavior of high-strength reinforced concrete columns with different transverse reinforcement detailing configurations. Engineering Structures , 291-301.
Lucchini , A., Franchin, P., & Sashi, K. (2016). Failure simulation of shear-critical RC columns with non-ductile detailing under lateral load. Earthquake Engineering Structural Dynamic , 855-874.
Megget, L. M. (1974). Cyclic Behaviour of Exterior Reinforced Concrete Beam-Column Joints. Bulletin of the New Zealand Naional Society for Earthquake Engineering, Vol 7 (1), 27-47.
Mo, Y., ASCE, & Wang, S. (2000). Seismic behavior of RC columns with various Tie Configurations. Journal of Structural Engineering, Vol. 126, 112-1130.
Mouzakis, H., & Kotsovou, G. (2012). Seismic design of RC external beam-column joints. Bull Earthquake Engineering , 645-677.
Mukherjee, A., & Joshi, M. (2004). FRPC reinforced concrete beam-column joints under cyclic excitation. Composite Structures , 186-199.
Oinam, R. M., Sahoo, D. R., & Sindhu, R. (2017). Cyclic Respose of Non-ductile RC Frames with Steel Fibers at Beam-Column Joints and Plastic Hinge Regions. Earthquake Engineering, 908-928.
Otani, S. (2002). Rose School short course on nonlinear analysis of reinforced concrete buildings. Italy: Rose School.
Pampanin, S., Magenes, G., & Carr, A. (2003). Modelling of Shear Hinge Mechanism in Poorly Detailed RC Beam-Column Joints. Athens: Concrete Strucutres in Seismic Regions.
Pan, Z. (2016). Modeling of Interior Beam-Column Joints for Nonlinear Analysis of Reinforced Concrete Frames. Michigan: ProQuest LLC.
Pantelides, C. P., Lawrence, R. D., Hansen, J., & Nadauld, J. (2002). Assessment of Reinforced Concrete Building Exterior Joints with Substandard Details. California : Pacific Earthquake Engineering Research Center.
Park, R., & Paulay, T. (1973). Behaviour of Reinforced Concrete External Beam-Column Joints Under Cyclic Loading. 782-781.
Park, S., & Mosalam, K. M. (2013). Experimental Investigation of Non-ductile RC Corner Beam-Column Joints with Floor Slabs. Structural Engineering, Vol 139 (1), 1-14.
Paulay, T. (1989). Equilibrium Criteria for Reinforced Concrete Beam-Column Joints. ACI Structural, Volumn 86 (6), 635-643.
Rajaram, P., Murugesan, A., & Thirugnanam, G. S. (2010). Experimental Study on behavior of Interior RC Beam Column Joints Subjected to Cyclic Loading. Internationa Journal of Applied Engineering Research, Volume 1 (1), 49-58.
Rajput, A., & Sharma, K. (2017). Seismic behavior of under confined square reinforced concrete columns. Structures 13, 26-35.
Renton, G. W. (1972). The Behaviour of Reinforced Concrete Beam-Column Joints Under Cyclic Loading. Christchurch : University of Canterbury .
Ricci , P., Luca, D., & Verderame, G. (2011). Reinforced Concrete Building Performance. Engrg Structures 9, 285-305.
Rodrigues, H., Arede, A., Varum, H., & Costa, A. (2012). Behavior of RC building column under cyclic loading: Experimental study . Journal of Earthquake and Tsunami; Vol 6, No. 4, 1-42.
Rodrigues, H., Varum, H., Arede, A., & Costa, A. G. (2013). Behavior of reinforced concrete column under biaxial cyclic loading-state of the art. International Journal of Advanced Structural Engineering, 1-12.
Said, A. M., & Nehdi, M. L. (2004). Use of FRP for RC Frames in Seismic Zones: Part I. Evaluation of FRP Beam-Coumn Joint Rehabilitation Technqiues . Applied Composite Materials, Volume 11, 205-226.
Said, A., & Nehdi, M. (2007). Behavior of reinforced self-consolidating concrete frames. Structures and Buildings 160, 95-104.
Schlaich, J., Schafer, K., and Jennewein, M. (1987). Toward a consistent design of reinforced concrete structures. PCI Journal, Vol. 32, No. 3, pp.74-150
Sezen, H., Elwood, K. J., Whittaker, A. S., Mosalam, K. M., Wallace, J. W., & Stanton, J. F. (2000). Structural Engineering Reconnaissance of the August 17, 1999 Earthquake: Kocaeli (Lzmit), Turkey" . California : PEER 2000/09.
Shafaei, J., Hisseini, A., & Marefat, M. S. (2014). Seismic retrofit of external RC beam-column joints by joint enlargement prestressed steel angles. Engineering Structures 81, 265-288.
Sheik, S., Shah, D., & Khoury, S. (1994). Confinement of high-strenght concrete columns. ACI Structural Journal, 101-111.
Subramania, D. (2015). Design of RC Beam Columns Joints. The Master Builder , 136-148.
Takahashi, S., Halim, S., & Toskatsu, I. (2014). Strength of Beam-Column Joint in Soft First Story RC Buildings Part 1: Experiment . Advanced Concrete Technology Vol 12, 138-145.
Tsai, K. C., Hsiao, C., & Bruneau, M. (2000). Overview of Building Damages in 921 Chi-Chi Earthquake . Earthquake Engineering and Engineering Seismology , 93-108.
Vaghani, M., Vasanwala, D. A., & Desai, D. K. (2015). Performace of RC Beam Column Connections Subjected to Cyclic Loading. Mechanical and Civil Engineering (IOSR-JMCE), Volume 12 (2), 48-53.
Varum, H. (2003). Seismic assessment, strengtheing and repair of existing buildings. Aveiro: University of Aveiro.
Vijayalakshmi, N., Kalaivani, M., Murugesan, A., & Thirugnanam, G. S. (2010). Experimentat Investigation of RC-Beam Column Joint Strengthening by FPP Wrapping . International Journal of Civil and Structural Engineering, 35-49.
Walkup, S. (1998). Rehabilitation of non-ductile reinforced concrete building columns using fiber reinforced polymer jackets . Pennsylvania: Lehigh University .
Wong, H. (2005). Shear strength and seismic performance of non-seismically designed reinforced concrete beam-column joints. Hong Kong: The Hong Kong University of Science and Technology .
Zhang, L and Jirsa, J.O. (1982) “A Study of Shear Behavior of Reinforced Concrete Beam-Column Joints”. PMFSEL Report No. 82-1, Department of Civil Engineering, University of Texas at Austin, 118pp.