Sandwich-structured composite

About: Sandwich-structured composite is a research topic. Over the lifetime, 5853 publications have been published within this topic receiving 101126 citations.

Dynamic compression of metallic sandwich structures during planar impulsive loading in water

Abstract: The compressive response of rigidly supported stainless steel sandwich panels subject to a planar impulsive load in water is investigated. Five core topologies that spanned a wide range of crush strengths and strain-dependencies were investigated. They included a (i) square-honeycomb, (ii) triangular honeycomb, (iii) multi-layer pyramidal truss, (iv) triangular corrugation and (v) diamond corrugation, all with a core relative density of approximately 5%. Quasi-statically, the honeycombs had the highest peak strength, but exhibited strong softening beyond the peak strength. The truss and corrugated cores had significantly lower strength, but a post yield plateau that extended to beyond a plastic strain of 60% similar to metal foams. Dynamically, the transmitted pressures scale with the quasi-static strength. The final transmitted momentum increased slowly with core strength (provided the cores were not fully crushed). It is shown that the essential aspects of the dynamic response, such as the transmitted momentum and the degree of core compression, are captured with surprising fidelity by modeling the cores as equivalent metal foams having plateau strengths represented by the quasi-static peak strength. The implication is that, despite considerable differences in core topology and dynamic deformation modes, a simple foam-like model replicates the dynamic response of rigidly supported sandwich panels subject to planar impulsive loads. It remains to ascertain whether such foam-like models capture more nuanced aspects of sandwich panel behavior when locally loaded in edge clamped configurations.

GFRP-Balsa Sandwich Bridge Deck: Concept, Design, and Experimental Validation

Abstract: The concept, design and experimental validation of the new Avancon Bridge in Bex, Switzerland, are described. The lightweight glass fiber-reinforced polymer (GFRP) sandwich bridge deck adhesively bonded to steel girders reduced the traffic disruption period by approximately 40 days or 80% compared to a cast-in-place concrete bridge and also enabled the bridge to be widened to two lanes. The semi-integral bridge concept allows the application of a continuous asphalt layer across the abutments without expansion joints and thus facilitates and reduces maintenance. The GFRP sandwich deck with structural balsa core fulfils all the requirements concerning serviceability, ultimate limit state and fatigue.

Investigations on sandwich core properties through an experimental–numerical approach

Abstract: Sandwich structures are increasingly used in the aerospace field, also for primary parts. However, due to the extensive manufacturing process, the evaluation of their precise mechanical behaviour is not straightforward. This evaluation is, at present, a key task to enable future exploitation of these structures. Numerical simulations are powerful and flexible tools to study and identify the mechanical behaviour of such components in detail. Thus, in the present work, an extensive and highly accurate identification/validation strategy based on experimental tests has been developed. Finite element simulations (virtual tests) have been carried out in order to investigate, in detail, the effect that several manufacturer’s parameters have on the crushing mechanics of sandwich panels containing a Nomex™ honeycomb core. Numerical scale modelling has also been evaluated with the aim to increase the understanding of the crushing phenomena, particularly the reciprocal effect of the cells.