Mississippi State University
Newman Jr, Jim
Date of Degree
Dissertation - Open Access
A weight function based modified strip-yield model is adapted to include the mode I effects of roughness induced crack closure. The weight function methodology is verified for arbitrary mixed mode loading conditions under load levels experienced in fatigue crack growth. A rough crack geometry is simulated as a sine wave fitted to a sawtooth defined by an asperity angle and period. Additional mode I crack closure due to mode II sliding of crack faces is calculated and incorporated into the strip-yield model by lengthening and shortening the crack face elements. Simulations of fatigue crack growth using the newly developed model are examined via a design and analysis of computer experiments. The effects of model parameters are identified. Combined roughness and plasticity induced crack closure for long cracks is studied.
Crapps, Justin Mandel, "Development Of A Macrostructural Model For Studying The Combined Effects Of Plasticity And Roughness Induced Crack Closure" (2010). Theses and Dissertations. 1415.