Assessment of seismic performance of RC frame structure with masonry infill panels partially uncoupled from the surrounding frame members

Abstract

The present study numerically analyses the influence of physical and mechanical properties of the materials used for masonry infill panels upon the seismic response of low rise reinforced concrete frame structure. A four-storey residential building (benchmark), located in Timisoara, a moderate seismic area, has been designed according to the current Romanian design codes. Then, infill panels considered uncoupled from the frame members along their lateral and upper edges, have been added to the structure. Infill panels have been investigated in four variants, by using 2 types of masonry units (hollowed ceramic blocks and AAC), alternatively built with mortars specific for regular bed joints (G) and thin bed joints (T), for which a comparative modal response spectrum analysis has been carried out. The seismic behaviour of buildings in all these cases has been analysed in terms of peak inter-storey drifts under two limit states and of the out-of-plane strength of infill panels. The results show that the peak inter-storey drifts reductions compared to the benchmark structure are up to 59% at SLS, and 61% at ULS. Regarding the out-of-plane behaviour of the infill panels it was noted that safety verification is fulfilled only for one of the abovementioned cases. As a final remark, the results obtained in this study highlight the importance of physical and mechanical properties of the masonry infill panels in the assessments of seismic response of frame structure buildings.