Optimizing sandwich beams for strength and stiffness

Abstract

This article presents a method for minimizing structural mass by optimizing the geometry and core density of sandwich beams comprising composite face sheets and polymer foam cores, loaded in three-point bending. The optimization is constrained by both strength and stiffness requirements. All possible locations in design space which might be global minima of mass are identified, and it is shown that, for a global minimum mass, at least two constraints must be simultaneously active. Calculations for a typical set of material properties are performed with the result that, for a wide range of standard materials, a minimum-mass sandwich beam satisfying both strength and stiffness requirements utilizes low-density foam and is constrained by stiffness and indentation strength.

Characterization Shear Properties of PVC Foams Instrumented by Optical Fiber under Flexural Loading

“…The strains magnitude already reached ±2000 microstrains without failure for 3-point bending test, 600 microstrains for 4A bending test and ±900 microstrains for 4B The main mode of collapse identified for the core beam in three-point and four-point bending is shear. This mode of core sandwich beam failure has been confirmed by numerous studies, including those of Chen et al [23] and Craig et al [24]. Obviously, the core is primarily selected to carry shear loading.…”

Review of balsa core sandwich composite structures

“…Sandwich structure design optimisation via analytical and finite element modelling is an important area of research [1,[96][97][98][99], but is beyond the scope of this review. Nevertheless, the cost-weight specific mechanical properties (Figure 10) combined with the sustainability benefits (Figure 7) of end-grain balsa make it an attractive choice of core material for many applications, especially those in which extremely lightweight high-performance core materials are not required.…”

Mechanical properties of multifunctional foam core materials

“…Therefore, flexural loadings have been extensively used in the literature in order to determine the core shear response [20,30,43,44,50,68,75,77,[85][86][87][88][89][90][91][92][93][94][95]. Therefore, flexural loadings have been extensively used in the literature in order to determine the core shear response [20,30,43,44,50,68,75,77,[85][86][87][88][89][90][91][92][93][94][95].…”