Crack arrest capabilities of an adhesively bonded skin and stiffener
The crack arrest capabilities and the load bearing characteristic of a stiffened and unstiffened panel subjected to remote tension loading is examined in this work. We make use of cohesive interface elements to predict the behavior of the center crack stiffened and unstiffened panels using a nonlinear traction-separation relationship. This thesis describes an application of traction-separation model on a four stringer stiffened wide panel with and without a disbond, and also an unstiffened panel with a center crack and compare their residual strengths. Aluminum 2024-T3 alloy panels were tested as a part of another study and the measured values were used to compare the numerical results. The predicted crack growth and residual predictions shows fair convergence with experimental values. The strength of the stiffened panel was observed to be much higher (55%) than that of that unstiffened panel. Moreover the presence of the disbond of 1” caused a 9% drop in the residual strength and disbond lesser than 1” does not lead to a drop in strength. The stiffened panel readily supported the transfer of load from the plate to the stiffener, thus aiding in the crack growth arrest.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering