Brian Justusson

Three-dimensional digital image correlation technique using single high-speed camera for measuring large out-of-plane displacements at high framing rates

We are concerned with the development of a three-dimensional (3D) full-field high-speed digital image correlation (DIC) measurement system using a single camera, specifically aimed at measuring large out-of-plane displacements. A system has been devised to record images at ultrahigh speeds using a single camera and a series of mirrors. These mirrors effectively converted a single camera into two virtual cameras that view a specimen surface from different angles and capture two images simultaneously. This pair of images enables one to perform DIC measurements to obtain 3D displacement fields at high framing rates. Bench testing along with results obtained using a shock wave blast test facility are used to show the validity of the method.

Dynamic Characterization of Textile Composites Part I: Uniaxial Tension

This two part series of papers will investigate the uniaxial and multiaxial response of textile composite materials subjected to high rates of loading. In this first paper, the uniaxial high rate tensile response of fiber tows commonly used in textile composites is studied. The rate dependent material response of IM7/SC-15 and S2 Glass/SC-15 are investigated in this work. The material is tested from quasi-static to dynamic rates using both a servo-hydraulic load frame and a split Hopkinson bar technique. Cross-ply laminates were investigated to determine the response due to the difficulty of preventing the splitting mode of failure for uni-composites. Stress–strain curves are generated and a discussion of the validity of results is framed by using DIC strain fields to examine the mechanics in the static and elevated rate regimes.