Study on time-dependent Seismic Fragility Analysis of RC Frame Structures Corroded by the most disadvantageous Chloride Attack
In this paper, the time-dependent fragility model is developed for corroding reinforced concrete (RC) frame. The developments represent a merger between a probabilistic model for chloride-induced corrosion and a time-dependent corrosion rate, and previously developed fragility model for undamaged RC frames designed by Chinese code. The loss of the cross sectional area of reinforcement bars, reduction of the cover and core concrete strength are modified by the single-factor time-dependent corrosion rate. Considering the cracking and spalling in the compressed concrete of compression zone caused by reinforcement corrosion, the modified compression-field (MCF) is used to predict the time-dependent compressed concrete strength. Finally, we employ SeismoStruct to obtain fragility estimates for the example frame based on the probabilistic models presented above. Three combined parameters (loss of the cross sectional area of reinforcement bars, reduction of the cover and core concrete strength) as a consequence of corrosion effects were calculated as a function of the corrosion rate for four different time periods (i.e., non-corroded (t=0), 5, 10and 15 years). The time-dependent fragility curves of three-floor RC frame in four ages corresponding to different performance levels are depicted by the IDA method based on the SeismoStruct. This method may be employed for the prediction of service-life and life-cycle cost analysis of RC frame structures.
School of Civil Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China
In this paper, the time-dependent fragility model is developed for corroding reinforced concrete (RC) frame. The developments represent a merger between a probabilistic model for chloride-induced corrosion and a time-dependent corrosion rate, and previously developed fragility model for undamaged RC frames designed by Chinese code. The loss of the cross sectional area of reinforcement bars, reduction of the cover and core concrete strength are modified by the single-factor time-dependent corrosion rate. Considering the cracking and spalling in the compressed concrete of compression zone caused by reinforcement corrosion, the modified compression-field (MCF) is used to predict the time-dependent compressed concrete strength. Finally, we employ SeismoStruct to obtain fragility estimates for the example frame based on the probabilistic models presented above. Three combined parameters (loss of the cross sectional area of reinforcement bars, reduction of the cover and core concrete strength) as a consequence of corrosion effects were calculated as a function of the corrosion rate for four different time periods (i.e., non-corroded (t=0), 5, 10and 15 years). The time-dependent fragility curves of three-floor RC frame in four ages corresponding to different performance levels are depicted by the IDA method based on the SeismoStruct. This method may be employed for the prediction of service-life and life-cycle cost analysis of RC frame structures.
郑山锁，杨威，秦卿，李磊,邓国专. 基于氯盐最不利侵蚀下锈蚀RC框架结构时变地震易损性研究[J]. 振动与冲击, 2015, 34(7): 38-45.
ZHENG Shan-suo, YANG Wei, Li Lei, Qin Qing，DENG Guo-zhuan. Study on time-dependent Seismic Fragility Analysis of RC Frame Structures Corroded by the most disadvantageous Chloride Attack. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(7): 38-45.
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