Comparison between the behavior of RCS and Concrete Moment Frames under Near Fault Earthquakes

Document Type : Technical note

Authors

Abstract

The composite RCS moment resisting frame, includes concrete columns and steel beams, it has some advantages in comparison to ordinary steel and concrete moment resisting frames. Previous studies have shown that these systems, in case of preserving sufficient strength and needed ductility in seismic condition, could be effective in design and construction. In the previous research on these structures, studies were made on the frame and RCS connections but there has not been any study on the seismic assessment of the RCS structure with time history and for the near fault earthquakes considering the effect of span length, for adopting this type of structure. Investigating the structure behavior under near the fault earthquake, due to the special nature and characteristics of these earthquakes in comparison to the far fault earthquakes seems to be essential. For this purpose 5 composite RCS intermediate moment resisting frames with 4, 7, 10, 15 and 20 stories and 5 spans were designed and then nonlinear dynamic analysis was performed on the structures using the OpenSees software. The obtained results in this research show that with increase in the number of stories the displacement of composite structure decreases with respect to the steel structure. The difference due to near and far fault earthquakes in calculation of stories displacement and drift in steel structures is far lower with respect to this difference in composite structures. This shows that effectiveness of near fault records on composite structures is more than the ordinary steel structures. Increase in the span length together with increase in the structure height would diminish the criticality of near fault record concerning the displacement of a composite structure which its columns have been made similar to the steel structure.

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[1] Deierlein, G.G. (1988). Design of moment connections for composite framed structures. University of Texas at Austin.
[2] Deierlein, G.G, Sheikh, T.M, Yura, J, Jirsa, J. (1989). Beam-column moment connections for composite frames: Part 2. Journal of Structural Engineering. 115(11), 2877-2896.
[3] Mehanny, S.S, Deierlein, G.G. (2001). Seismic damage and collapse assessment of composite moment frames. Journal of Structural Engineering, 127(9), 1045-1053.
[4] Cordova, P. and Deierlein, G.G. (2005). Validation of the seismic performance of composite RCS frames: full-scale testing, analytical modeling, and seismic design. PhD Dissertation. The John A. Blume Earthquake Engineering Center Dept. of Civil and Environmental Engineering Stanford University.
] 5 [ یزدانی، آ. ) 1321 (. ارزیابی لرزهای و بررسی رفتار خطی و غیرخطی سازههای مرکب )کامپوزیت( فولادی و بتنی مسل . ح پایاننامه کارشناسی ارشد.
دانشگاه علم و صنعت ایران، تهران.
] 1 [ اسکندریان، ف. ) 1304 (. بررسی رفتار خطی و غیرخطی قابهای مهاربند شده مرکب RCS . پایان نامه کارشناسی ارشد، دانشگاه سمنان، سمنان.
[7] Chen, C-H. Lai, W-C. Cordova, P. Deierlein, G.G. Tsai K-C. (2003). Pseudo-dynamic test of full-scale RCS frame: Part I: Design, Construction and Testing. in Proceedings of International Workshop on Steel and Concrete Composite Constructions.
[8] Cordova, P. Chen, C-H. Lai, W-C. Deierlein, G.G. Tsai, K-C. (2004). Pseudo-dynamic test of full-scale RCS frame: Part II: Analysis and design implications. in Proceedings of the 2004 Structures Congress.
] 0 [ طالبیان ن. ) 1320 (. ارزیابی لرزه ای قاب های RCS . پایان نامه کارشناسی ارشد، دانشگاه تبریز، تبریز.
[10] OpenSees, (2009). Open System for Earthquake Engineering Simulation, Available at: http://opensees. Berkeley. Edu.
[11] ACI 318-08. (2008). Building Code Requirements for Structural Concrete and Commentary. Portland Cement Association-American Concrete Institute.
[12] AISC 360-05. (2005). Specification for Structural Steel Buildings. American Institute of Steel Construction. A ANSI - Inc: Chicago, IL.
[13] ASCE 7-10. (2010). Minimum Design Loads for Buildings and Other Structures. American Society of Civil Engineers, ISBN 978-0-7844-1085-1.
] 14 [ - .) کمیته دائمی بازنگری آیین نامه طراحی ساختمان ها در برابر زلزله. ) 1324 (. آیین نامه طراحی ساختمان ها در برابر زلزله )استاندارد 02 2211
ویرایش چهارم، تهران، مرکز تحقیقات ساختمان و مسکن.
[15] http://ngawest2.berkeley.edu/ [Online].
[16] FEMA-356. (2000). Prestandard and Commentary for the Seismic Rehabilitation of Buildings, ASCE (Funded by Federal Emergency Management Agency).
[17] http://seismosoft.com/en/Download.aspx .