| Title |
Mixed Mode Analysis using Two-step Extension Based VCCT in an Inclined Center Crack Repaired by Composite Patching |
| Authors |
안재석(Ahn, Jae-Seok) ; 우광성(Woo, Kwang-Sung) |
| DOI |
https://doi.org/10.12652/Ksce.2012.32.1A.011 |
| Keywords |
p-수렴 부분 층별모델;팻치보강적층판;혼합모우드;가상균열닫힘법;2단계 확장법 p-convergent partial layerwise model;patch-repaired laminate plate;mixed mode;VCCT;two-step extension method |
| Abstract |
This paper deals with the numerical determination of the stress intensity factors of cracked aluminum plates under the mixed mode of $K_I$ and $K_{II}$ in glass-epoxy fiber reinforced composites. For the stress intensity factors, two different models are reviewed such as VCCT and two-step extension method. The p-convergent partial layerwise model is adopted to determine the fracture parameters in terms of energy release rates and stress intensity factors. The p-convergent approach is based on the concept of subparametric element. In assumed displacement field, strain-displacement relations and 3-D constitutive equations of a layer are obtained by combination of 2-D and 1-D higher-order shape functions. In the elements, Lobatto shape functions and Gauss-Lobatto technique are employed to interpolate displacement fields and to implement numerical quadrature. Using the models and techniques considered, effects of composite laminate configuration according to inclined angles and adhesive properties on the performance of bonded composite patch are investigated. In addition to these, the out-of-plane bending effect has been investigated across the thickness of patch repaired laminate plates due to the change of neutral axis. The present model provides accuracy and simplicity in terms of stress intensity factors, stress distribution, number of degrees of freedom, and energy release rates as compared with previous works in literatures. |