Fragility analysis of masonry infill R.C. frame using incremental dynamic approach

Abstract

The current study aims to investigate damage assessment of the RC frames with brick masonry infill (BMI). The effects of near-source ground motions (GMs) are considerably predominant in the seismic response of the structure as related to far-source ground motion due to their forward directivity plus long period. The near-source ground motion is characterized by enormous everlasting ground translation, strong peak ground acceleration (PGA), and a very low-frequency pulse. The Indian codes have not yet incorporated the influence of near-source GM into their design response spectra. Hence, IDA curves that represent ground motion uncertainty have been established for ten near-field ground motion records. Further, the fragility curves have been constructed to envisage progressive damage to the structure. The spectral acceleration-based fragility curves for the ten-story RC frames without BMI, with BMI, and with the open ground story are developed. It is proved that the BMI frame shows better performance during seismic motions. The probability of damage for the collapse prevention state is reduced for frames with BMI, and with open-ground story frames as compared to a frame without BMI.