STRENGTHENING OF MASONRY SHEAR WALLS BASED ON METAL SOLUTIONS. PART I: EXPERIMENTAL INVESTIGATION

Due to the lack of resistance, to a small deformation capacity and to a low ductility, many masonry buildings in prone seismic areas may need structural interventions. Innovative interventions which will increase the wall capacity and ductility, without a major influence on its stiffness, may be valuable. A number of experiments attempting to establish the retrofitting technique efficiency will be detailed in the article. The proposed technique applies metallic plates as external reinforcing. They are connected by means of chemical anchors or pretension threaded rods, onto one or both sides of the wall. The solution can be applied to internal shear walls and on facades either on piers or spandrel. An important technique advantage may be the reversibility provided by dry steel connections. Limited damage occurs after uninstalling (except for the holes in the walls). Metal sheath reinforced masonry walls have complex behaviour and no analytic rules for design are available. Advanced numerical models confirmed by enlarged experimental tests are needed. All experimental tests were performed within the framework of the PROHITECH research project. Tests on component materials, in 500 x 500 mm and 1500 x 1500 mm retrofitted masonry elements, were done.