DAMAGE DEVELOPMENT IN A SIDEGROOVED CT SPECIMEN BASED ON A 3-D ENDOCHRONIC DAMAGE MODEL

This paper presents a three-dimensional crack initiation analysis in a sidegrooved CT specimen. This is achieved with an endochronic damage model proposed recently by Chow and Chen [1,2] and discretized for fin ite element analysis. The damage model enables the quantification of t he progressive damage evolution which would not be otherwise possible using the conventional fracture mechanics analysis. By employing two s eparate damage failure criteria, the crack is predicted to initiate at a small distance from the sidegroove and the prediction agrees well w ith the experimental observation. A more uniform crack initiation acro ss the crack-tip line is observed both experimentally and theoreticall y relative to the CT specimen without sidegrooving.