INELASTIC RESPONSE OF MASONRY INFILLED REINFORCED CONCRETE STRUCTURES

It is well known that masonry infill walls, although non-engineered and considered as non-structural, may provide most of the earthquake resistance and prevent collapse of relatively flexible and weak RC structures.The objective of this study is to investigate the effect of masonry infill walls with openings on the performance of reinforced concrete frames under lateral loads.Specifically, this study is concerned with the evaluation of inelastic parameters of masonry infilled reinforced concrete buildings.Buildings with various heights are selected and designed according to EC8.Inelastic pushover analyses are performed and local and global strength and inelastic deformation characteristics are evaluated.The influence of various parameters, such as the number of storeys, the distribution of infill walls, their strength and their opening percentage on the seismic response of the buildings is thoroughly examined.The results from nonlinear pushover analyses indicate that the overstrength and ductil ity of RC buildings can be higher than the values considered in the design.The presence of infill walls increases considerably the stiffness of the structures and their global resistance to lateral loads.However, the irregular distribution of infills (soft storey -case of pilotis) significantly reduces the capacity of the structure.