It is acknowledged that masonry walls in RC frame structures greatly affect the seismic resistance of buildings. Their contribution toward seismic response improvement is proportional to their participation level on buildings. The more abundant they are on buildings, their lateral strength contribution gets more significant, especially for 'frame systems' of both RC and Steel structures. However, due to their anisotropic, heterogeneity features and high margin of variation in mechanical characteristics, their effect on the seismic response of buildings is quite complicated. Often times, on-site investigation of buildings affected by strong earthquakes demonstrated a premature failure of masonry wall panels (out-of-plane and tension failures) which triggered undesired negative effect on the seismic performance of buildings. Consequently, masonry walls are generally omitted in the analytical modelling stage of building analysis and design.
This paper elaborates an “innovative” solution which aims to provide a reliable seismic protection to masonry walls and to improve the seismic performance of the entire building structure. These goals are achieved through use of innovative friction&sliding seismic devices’. These “box-like” devices are placed at characteristic locations between the masonry infill walls and the structural frame system of the building. They act as special link elements joining the top of wall panels and the bottom of beams and/or slabs. The assemblage of a wall panel, IDRIZI seismic devices and other boundary structural elements form an integral structural system that is simply called “IDRIZI” frame/wall system.
A study involving both experimental and analytical research, showed that on buildings integrated with IDRIZI frame/wall system, up to 80% of earthquake energy input in the structure could be dissipated by the friction mechanism of the IDRIZI devices. This solution provides remarkable improvements on the seismic performance of residential buildings (both existing or newly constructed) or any other type of building where masonry walls are abundantly present.