The simulated earthquake response of two 7-story R.C. planar model structures - A shear wall and a frame with masonry infills

摘要

Two geometrically similar but structurally very different reinforced concrete planar model structuresare examined here; one is a 7-story shear wall and the second is a 7-story frame with or withoutmasonry infills. The observed performance for these two models is discussed, based on comparisonsrelated to the dominant response frequencies and to the measured story drifts, base shearand overturning moment. The initial stiffness of the frame model, due to the presence of the masonryinfills, was approximately 40% of that of the shear wall; however, it degraded very much assoon as diagonal cracking of the infill occurred. Thus, for moderate earthquake loads, masonry infilledframes may retain an initial high stiffness, which is expected to become much lower after theappearance of damage in the infills. The initial stiffness for the shear wall also degraded during thelarge displacement response stage, accompanied by moderate damage at the base of the wall. Themeasured maximum base shear of the shear-wall was more than twice that of the frame whereas themaximum overturning moment for the shear wall was 50% larger than that of the frame.