In the framework of passive control devices for the seismic protection of new and existing buildings, in the last years large attention has been focused on shear wall systems. They are based on the use of a series of steel plates which realise a stiffened central nucleus able to absorb the horizontal action effect. These devices, which are obtained by inserting a steel panel within an external reaction steel frame, have a low realization cost and high speedy of erection. They can be classified in two main categories: - panels acting on the stiffness and the strength of the main structure; - panels having a dissipative function.
The Steel Plate Shear Walls (SPSW), belonging to the first typology, are characterised by slender steel plates. They have been largely used in the last years in North America and Japan as an effective device against seismic actions.
The behaviour of such system is strongly conditioned by buckling phenomena occurring at the early stages of the loading process. Such phenomena may have a significant influence also on the ultimate strength of the system, despite the development of stable post-critical behaviour due to the well known tension field mechanism. The theoretical and numerical studies on the behaviour of these devices confirm the reliability of the structural system when specific geometrical ratios of the panel are respected, i.e. for panels having b/d ratio raging from 0.8 to 2.5 [
]. In this paper, the theoretical behaviour of steel panels in shear, based on existing simplified methodologies (strip model theory) [
] is analysed and then compared with the results obtained by an extensive numerical study carried out using sophisticate finite element models (implemented in the ABAQUS non linear code). The comparison between theoretical and numerical results has been developed with reference to different values of the late thickness and varying the
ratio. In addition, the influence of intermediate stiffeners is analysed. In the whole the obtained results provide useful information for the correct design of slender steel plates in shear to be used as stiffening devices in new and existing framed structures.