Experimental tests and optimization rules for steel perforated shear panels

The paper presents the main results obtained downstream experimental and numerical study on steel perforated shear panels. Primarily, the response of the studied devices determined by cyclic tests is analysed. It is evidenced that the hysteretic performance of steel perforated shear panels might be detrimentally influenced by pinching effects and softening due to cumulated damage produced by lateral-torsion buckling that may arises when the plate portions delimited by contiguous perforations are excessively slender. Based on tests results, a suitable analytical formulation for the prediction of the strength at several shear demands, accounting for the influence of the above detrimental effects, is provided. Also, a parametric study based on a FEM numerical model calibrated on the basis of the experimental tests is developed. Two main goals are achieved: i) to establish the influence of the main geometric parameters on the panel hysteretic response, with particular regard to the pinching effects provoked by buckling phenomena; ii) to determine analytical formulations able to give back the ratio between the "pinching" strength and the maximum strength, the former being the force corresponding to a null shear strain in a cycle. Therefore a useful predictive tool for defining the optimal perforation geometry to be adopted as a function of the expected shear demand is provided.