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.
A discrete cohesive zone model (DCZM) is implemented to simulate the mode I fracture of two dimensional triaxially braided carbon (2DTBC) fiber composites. The 2DTBC is modeled as an elastic-one-parameter (a66) plastic continuum. The plastic behavior of the 2DTBC was characterized by measuring a66. Mode I fracture tests are carried out by using a modified single edge notch bend (SENB) configuration. Fracture toughness (GIC) as a function of crack extension is measured by a compliance approach. The fracture tests are then simulated by using the DCZM based interface element in conjunction with the commercial software ABAQUS® through a user subroutine UEL. The simulated results, carried out under conditions of plane stress, are compared with the experimental results and also verified for mesh sensitivity. The results presented provide guidelines and a basic understanding to model structural response of non-homogeneous materials, incorporating fracture as a damage mechanism and using constituent level material properties, geometry, and fracture toughness (GIC) as input.