Digital Image Correlation (DIC) is an easy to use yet powerful approach to measure displacement and strain fields. While the method is robust and accurate for a variety of applications, standard DIC returns large error and poor correlation quality near displacement discontinuities such as cracks or shear bands. This occurs because the subsets used for correlation can only capture continuous def...

in this paper, a higher order continuum model is presented based on the cosserat continuum theory in 3d numerical simulation of shear band localization. as the classical continuum models suffer from the pathological mesh-dependence in strain softening models, the governing equations are regularized by adding the rotational degrees-of-freedom to conventional degrees-of-freedom. the fundamental r...

This paper proposes a novel metal additive manufacturing process, which is composition of gas tungsten arc (GTA) and droplet deposition (DDM). Due to complex physical metallurgical processes involved, such as impact, spreading, surface pre-melting, etc., defects, including lack fusion, overflow discontinuity deposited layers always occur. To assure the quality GTA-assisted DDM-ed parts, online ...

A condition for the emergence of a discontinuity in an elastic peridynamic body is proposed, resulting in a material stability condition for crack nucleation. The condition is derived by determining whether a small discontinuity in displacement, superposed on a possibly large deformation, grows over time. Stability is shown to be determined by the sign of the eigenvalues of a tensor field that ...

Laboratory experiments were performed on cubic samples of Austin Chalk to investigate the effect of fabric-induced anisotropy on the interpretation of fracture specific stiffness. The experimental results found that the fabric-induced layering complicates the interpretation of fracture specific stiffness. Seismic measurements from a sample with small layers (i.e., spacing and thickness) show th...

Considered is the interaction of macro-and micro-cracks in an anisotropic piezoelectric solid. The GreenÕs function and principle of superposition are used to formulate a system of singular integral equations for solving the unknown temperature discontinuity and elastic displacement-electric potential. The residual heat ̄ux, stress and electric displacement on the microcrack are evaluated direc...