When considering structural failure during an impact, the energy that can be absorbed by the material can be more important than its ultimate static strength. Often the dynamic energy absorption is assumed to be approximated by the strain energy accumulated during a quasi-static test before failure, which depends as much on the elongation at break as on the maximum load sustained. As a result, for core materials, the shear elongation at break has thus become considered to be as important a property as ultimate shear strength.
Nonetheless, it has also been found that the transient nature of impact loads can cause stress and strain rates that are high enough to affect the behaviour of the core material, including the resulting strength, particularly for polymeric foams. As a result, the static energy absorption is still a qualitative indication of the likely dynamic behaviour of a core material, but cannot be taken as a quantitative measure of the dynamic property by itself.
The aim of this project is to build on existing mechanical testing at a coupon scale to understand how these dynamic influences affect performance in real-world structures.
Undergraduate
None
No lab has been assigned to this project