doi:10.3850/978-981-08-7920-4_S2-S22-cd

ABSTRACT

One of the main challenges in earthquake risk mitigation nowadays is the seismic performance assessment of existing buildings that were not designed according to modern building code standards and the development of effective techniques to retrofit these structures. In this paper seismic performance of an existing 5-story RC frame building which is typical building stock in central region of Tehran retrofitted by three methods (Concrete jacketing, Steel jacketing, CFRP wrapping) is investigated by developing fragility curves. Corresponding Fragility curves are constructed for three structural damage limit states, collapse prevention (CP), Life Safety (LS) and immediate occupancy (IO) and fragility curves of retrofitted frames are compared to the original frame for evaluation of seismic performance improvement. For this purpose series of Incremental Dynamic Analysis (IDA) using 20 accelerograms are performed by SeismoStruct software. In the dynamic analysis the structural members are modeled by employing distributed plasticity fiber element and both geometrical and material nonlinearity are taken into account. The results help stakeholders to select the suitable retrofit strategy for an existing RC frame considering economical issue.

Keywords: Fragility curve, Incremental dynamic analysis, Seismic retrofit, RC frame concrete jacketing, Steel jacketing, FRP wrapping.

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