Cyclic testing of a single bay reinforced concrete frames with various types of masonry infill

In this paper a contribution of various types of masonry infill to the behaviour of reinforced-concrete frames under lateral loads is presented. As a part of the bigger project, ten one-bay, one storey reinforced-concrete frames were designed according to the EC8, built in a scale 1:2.5, infilled with masonry and tested under constant vertical and cyclic lateral load. The masonry wall had various strength properties, namely: high strength hollow clay brick blocks, medium strength hollow clay brick blocks and low strength lightweight Autoclaved-aerated concrete blocks. There were no additional shear connectors between the masonry and frame. The results showed that the composite “framed-wall” structure had much higher stiffness, damping and initial strength than the bare frame structure. Masonry infill filled-in the load capacity gap from very low (0, 05%) to drifts when the frame took over (0, 75%). The structures behaved as linear monolithic elements to drifts of 0, 1%, reached the maximum lateral capacities at drift of 0, 3%, maintained it to drifts of 0, 75% and after that their behaviour depended on the frame. Masonry infill had severe damage at drift levels of about 0, 75% but contributed to the overall system resistance to drifts of about 1%. At that drift level the frame had only minor damage and was tested to drifts of about 2% without any loss of capacity. Improvement of the “infills provisions” in the codes could be sought by taking into account the contribution of a common masonry that reduces expected damages by lowering the drift levels.