Investigating Deterioration Effect of Hysteresis Loops in Nonlinear Static Analysis of Intermediate RC Moment Frame

Document Type : Research Article

Authors

Abstract

This research investigates the effect of stiffness degradation, strength deterioration and pinching behavior of hysteresis loops in static nonlinear analysis. One of the inefficiencies of static nonlinear analysis is that nonlinear behavior of structural elements due to cyclic deformations is approximately considered in the analysis, and only one quarter of a full hysteretic loop is considered. For investigating the effect of this inefficiency in analysis results, three intermediate concrete moment frames from regular RC structures are selected. The performed procedures in FEMA-356 and proposed plastic hinges in this guideline are utilized for performing static nonlinear analysis. A coefficient for consideration of stiffness degradation and strength deterioration is proposed by FEMA-356 in nonlinear static analysis. This coefficient for intermediate RC moment frames is equal to unity. For calculation of this coefficient, in this paper, the nonlinear dynamic analysis is used. Clough and Takeda Hysteretic loops and a hysteretic loop that considers effects of severe stiffness degradation, strength deterioration and pinching are assumed in nonlinear dynamic analysis. Comparing final results lead to conclusion that revealed the value of this coefficient is obtained 25% more than the value proposed by FEMA-356.

Keywords

References

[1]آیین نامه طراحی ساختمان ها در برابر زلزله استاندارد ۲۸۰۰ – مرکز تحقیقات ساختمان و مسکن،. ویرایش سوم، ۱۳۸۴
[2] دستورالعمل بهسازی لرزه ای ساختمانهای موجود، سازمان مدیریت و برنامه ریزی کشور، دفتر امور فنی . و تدوین معیارها، خرداد ۱۳۸۱
[3]Applied Technology Council; Seismic Evaluation and Retrofit of Concrete Buildings, Volume 1,ATC-40 Report, Redwood City, California, 1996.
[4]Federal Emergency Mnagement Agency; Prestandard and Commentary for the Seismic Rehabilitation of Buildings, FEMA356,
Washington, D.C., 2000.
[5]Kunnath, S. K.; Reinhorn, A. M.; Lobo, R. F.; “IDARC: A Program for the Inelastic Damage Analysis of Reinforced Concrete Structures”,Report No. NCEER-92-0022, National Center for Earthquake Engineering Research, State University of New York at Buffalo, 1992.
[6]Computer & Structures Inc., “Linear and Nonlinear Static and Dynamic Analysis and Design of Building Systems Users Guide, ETABS Ver. 9”,Berkeley, California, 2005.
[7]ACI Committee 318, " Building Code Requirements for Structural Concrete and Commentary (ACI 318M-05)", American Concrete
Institute.
[8]Park, Y.J., Reinhorn,A.M., Kunnath,S.K., "IDARC: Inelastic Damage Analysis of Reinforced Concrete Framed-Shear Wall Structures", NCEER-87-0008, 1987.
[9]Clough, R.W., Benuska, K.L. and Wilson, E.L., "Inelastic Earthquake Response of Tall Buildings",Proceedings, Third World Conference on Earthquake Engineering, New Zealand, Vol.11,New Zealand National Committee on Earthquake Engineering, 1965.
[10]Takeda, T., Sozen,M.A. and Nielsen, N.N., "Reinforced Concrete Response to Simulated Earthquakes", Journal of the Structural Division,ASCE, Vol. 96, ST12, Dec. 1970.
[11]Bathe,K.J, "Finite Element Procedure", Prentice- Hall, 1996

Files

Share

How to cite

Statistics