PARAMETRIC STUDY AND DESIGN FORMULATION OF ALUMINIUM DAMPERS

Abstract

The energy dissipation potential of a metallic damper depends mostly on the hysteretic response attained due to the inelastic deformation of plates under axial or flexural or shear loading. Mainly considering the metallic damper under shear loading, that is generated by the lateral loads of the structure. Shear panels yielding can be used to dissipate energy by hysteresis provided if the strength deterioration occurred by inelastic buckling is controlled. In the present study, the model is analytically examined ‘cyclic inelastic buckling of aluminium panels in edge shear. ‘Widely available aluminium alloy 6063, which is widely used for structural applications, was used as material of damper which is I-shaped specimens’. One hundred and fifty models of aluminium panels were generated with different geometric parameters, like web thickness, spacing of stiffeners, flange thickness, web length, web depth, stiffener thickness and number of panels which affect in the inelastic buckling. All the models were tested under reversed cyclic loading with increasing displacement levels. The buckling tendency of the panel is retarded on increasing web depth-to thickness ratio and reducing its aspect ratio. The models exhibited very ductile behaviour and very good energy dissipation potential with un-pinched and full hysteresis loops with shear strains up to 0.2 when element deletion value is 0.8 and shear strain up to 0.1 when element deletion value is 0.6 respectively. The analytical data set was used to acquire the proportionality factor in Gerard’s formulation of inelastic buckling. The results are further used to obtain a relation between panel aspect ratio, the web panel depth-to-thickness ratio, and web buckling deformation angle for cyclic inelastic buckling, that can be used to determine the stiffener spacing, which limits the inelastic web buckling at design shear strains