Seismic Response of Reinforced Concrete Frames with Masonry Infills

Abstract

Reinforced concrete (RC) frames with masonry infills are one of the most commonly used structural systems in the world, especially in the regions susceptible to earthquake. The infill walls are generally not considered as a structural element in seismic codal provisions. But it might be not profitable to neglect the role of infills. Moreover, the infilled masonry panels may considerably affect the stiffness and strength of RC frames. In the past few decades, great losses in lives and properties are witnessed in RC framed structures under the action of earthquakes, thus depicting the vulnerability of these structures. Over the past few years, extensive research has been carried out to study the behaviour of RC structures under seismic loading. Experimental investigations of RC frames with masonry infills are carried out to determine their complex seismic performance. However, these experimental tests are significantly expensive and are thus performed less in quantity. Hence, this study focuses on the analytical investigation on masonry infilled RC frame structures under seismic loading using computer programme ETABS. In this investigation, 3 eight storeyed planar frames are considered, namely bare frame (BF), fully infilled frame (IF), and open ground storey frame (OGSF). The masonry infill is modelled as an equivalent diagonal strut conforming to IS 1893:2016. The frame models are subjected to response spectrum analysis and time history analysis. The response of the structures was observed in terms of storey displacement, inter-storey drift, base shear, and various other parameters. All the analysis performed has shown that the inclusion of masonry infill in RC frames affect stiffness, strength, and displacement of these structures.