摘要
Considering failures during machinery processes such as drilling,a precautionary analysis involving delamination and the corresponding dissipated energy is required,especially for composite structures.In this context,because of the complexity of both the analysis procedure and experimental test setup,most studies prefer to represent mode Ⅰ and Ⅲ interlaminar crack propagation instead of that involving mode Ⅱ.Therefore,in this study,the effect of mode Ⅱ delamination and corresponding interlaminar crack propagation was considered during the drilling process of multilayered glass/polyester composites using both numerical and experimental approaches.In the experimental procedure,the mechanical properties of the glass/polyester specimens were obtained according to ASTM D3039.In addition,the interlaminar mixed-mode(Ⅰ/Ⅱ)loadings were determined using an ARCAN test fixture so that the fracture toughness of glass/polyester could then be identified.The mode Ⅱ critical strain energy release rate(CSERR)was then obtained using an experimental test performed using an ARCAN fixture and the virtual crack closure technique(VCCT).It was determined that the numerical approach was in accordance with the experiments,and more than 95%of crack propagation could be attributed to mode Ⅱ compared to the two other modes.
