Proposed formulas for evaluation of the equivalent material properties of a multiholed structure

It is widely known that the development of fine mesh in the immediate vicinity of the holes in a multiholed plate is a challenging issue. In practice, due to the amount of time consumed and the quality of the modelling, it is not desirable to model the structural characteristics of a multiholed plate in detail. In this regard, an effective means by which to avoid the unnecessary work of simulating a multiholed plate is to replace it with an equivalent solid plate while considering the decrease in stiffness associated with the increasing area of the holes. The objective of this study is to numerically and experimentally investigate the equivalent material properties of a multiholed plate of stainless steel 316L with respect to ligament efficiencies. Simple design formulas are proposed to determine the equivalent material properties of a multiholed plate that is completely perforated with closely spaced circular holes in a square or diagonal pattern by means of nonlinear finite-element method computations. It is concluded that the proposed formulas are accurate for prediction of the equivalent material properties of multiholed structures for their design and engineering.