The Effect of Site Seismic Hazard on Selection of a Retrofitting Method for a Deficient Reinforced Concrete Frame

Document Type : Research Article

Authors

Department of Civil Engineering, K.N.Toosi University, Tehran, Iran

Abstract

One aspect of Performance Based Earthquake Engineering (PBEE) is to allow comparison between different designs and retrofit solutions using estimation of collapse probability. To investigate this process, case study was performed on the weak RC frame that has been retrofitted with two different methods, e.g., brace and cylindrical friction damper. Models of case study were defined in OpenSees software. Then 15 ground motions were selected and Incremental Dynamic Analysis (IDA) was conducted on models. The performances of buildings were evaluated by using a probabilistic analysis. The results show that, the retrofit methods reduces the possibility collapse in both performance levels, IO and CP. However, considering site-specific seismic hazard curve in which the reduction of structure period was included, the different results were obtained. In this study, although the collapse probabilities for a specific hazard level for both retrofitting schemes were reduced, the collapse probability of the structure retrofitted with brace in CP level increased in comparison with the initial structure.

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[1] Y. Zhou, X. Lu, D. Weng, R. Zhang, A practical design method for reinforced concrete structures with viscous dampers, Engineering structures, 39 (2012) 187-198.
[2] M.R. Maheri, H. Ghaffarzadeh, Connection overstrength in steel-braced RC frames, Engineering Structures, 30(7) (2008) 1938-1948.
[3] K. Viswanath, K. Prakash, A. Desai, Seismic analysis of steel braced reinforced concrete frames, International Journal of civil and structural engineering, 1(1) (2010) 114
[4] J. Conner, Introduction to Structural Motion Control, Prentice Hall, 2002.
[5] C.M. Ramirez, Building-specific loss estimation methods & tools for simplified performance-based earthquake engineering, Stanford University, 2009.
[6] S. Mazzoni, F. McKenna, G.L. Fenves, OpenSees command language manual, Pacific Earthquake Engineering Research (PEER) Center, 264 (2005).
[7] Recommended Seismic Design Criteria for New Steel Moment-frame buildings, FEMA-350, 2000
[8] M. Mirtaheri, A.P. Zandi, S.S. Samadi, H.R. Samani, Numerical and experimental study of hysteretic behavior of cylindrical friction dampers, Engineering Structures, 33(12) (2011) 3647-3656.
[9] N. Shome, Probabilistic seismic demand analysis of nonlinear structures, 1999
[10] F. Jalayer, Direct probabilistic seismic anaysis: implementing non-linear dynamic assessments, Stanford University, 2003.
[11] D. Vamvatsikos, C.A. Cornell, Incremental dynamic analysis, Earthquake Engineering & Structural Dynamics, 31(3) (2002) 491-514.
[12] F. Zareian, H. Krawinkler, L. Ibarra, D. Lignos, Basic concepts and performance measures in prediction of collapse of buildings under earthquake ground motions, The Structural Design of Tall and Special Buildings, 19(1-2) (2010) 167-181.
[13] Nehrp Guidelines for the Seismic Rehabilitation of Buildings,FEMA 273, 1997.
[14] F. Jalayer, C.A. Cornell, A technical framework for probability-based demand and capacity factor (DCFD) seismic formats.” RMS, (2003).