Investigation of Mixed-Mode I/II Fracture under Impact Loading Using Split-Hopkinson Pressure Bar

Using the split Hopkinson pressure bar to validate material models.

This paper gives a discussion of the use of the split-Hopkinson bar with particular reference to the requirements of materials modelling at QinetiQ. This is to deploy validated material models for numerical simulations that are physically based and have as little characterization overhead as possible. In order to have confidence that the models have a wide range of applicability, this means, at...

A Tensile Split Hopkinson Bar for Testing Particulate Polymer Composites Under Elevated Rates of Loading

A tensile split Hopkinson bar apparatus is developed for testing high strain rate behavior of glass-filled epoxy. The apparatus uses a specimen gripping configuration which does not require fastening and/or gluing and can be readily used for castable materials. Details of the experimental setup, design of grips and specimen, specimen preparation method, benchmark experiments, and tensile respon...

Stress Equilibrium in the Split Hopkinson Pressure Bar Test

The compressive split Hopkinson pressure bar (SHPB) technique allows the stresses on each end of the specimen to be measured individually. Results are presented showing a large difference between these end pressures, depending on specimen length and loading rate. The mechanisms responsible are shown to be a combination of inertial forces and non-uniform deformation due to wave propagation. Impl...

Advancements in the Split Hopkinson Bar Test

High Rate Characterization of Low Impedance Materials Using a Polymeric Split Hopkinson Pressure Bar

The characterization of soft or low impedance materials is of increasing importance since these materials are commonly used in impact and energy absorbing applications. There is a need to measure the high-rate material properties of soft materials, where the mode of loading is predominantly compressive and large deformations may occur at high rates of deformation. Importantly, the competing eff...