... laminates because of the strong transverse effect from adjacent plies. A smeared properties approach is more robust for the strain energy release rate analysis of delamination between ±45-degree angle ply laminates. The three-dimensional analysis indicates that delamination failure between the stiffener...

... of the study are summarized in recommendations for the MMB test procedure and its subsequent evaluation. composite materials mixed-mode bend test strain energy release rate Mode I Mode II delamination tests fracture mechanics beam theory> References Reeder , J. R. and Crews , , J...

... near the loading point a small Mode II component exists. However, the magnitude of this Mode II strain energy release rate at the loading point is small compared to the magnitude of Mode III component in the mid-section of the specimen. Hence, the ECT test yielded the desired Mode III delamination...

...J Li; TK O’Brien Simplified expressions for the parameter controlling the load-point compliance and strain energy release rate were obtained for the edge crack torsion (ECT) specimen for Mode III interlaminar fracture toughness. Data reduction methods for Mode III toughness based on the present...

...TF Walsh; CE Bakis The double cantilever beam (DCB) test was used to determine the effects of high-temperature degradation on the Mode I critical strain energy release rate ( G IC ) of a continuous fiber-reinforced polymer-matrix composite material. The composite material investigated was IM7/8551...

...W Cui; MR Wisnom; MI Jones Strain energy release rate criteria are often used for predicting delamination. However, the fracture energy for delamination propagation is not a material constant, but varies depending on the through thickness normal stress. For tensile normal stresses this problem...

...TK O'Brien An analysis using laminated plate theory is developed to calculate the strain energy release rate associated with local delaminations originating at off-axis, angle-ply, matrix cracks in laminates subjected to uniaxial loads. The analysis includes the contribution of residual thermal...

... the longevity of structures manufactured from composite materials. Douglas S. Cairns 1 Static and Dynamic Mode II Strain Energy Release Rates in Toughened Thermosetting Composite Laminates REFERENCE: Cairns, D. S., "Static and Dynamic Mode II Strain Energy Release Rates in Toughened Thermosetting Composite...

...EA Armanios; LW Rehfield; IS Raju; TK O'Brien A validation of the sublaminate analysis method developed earlier is provided in this work by comparison of the predictions with a quasi-three-dimensional finite element analysis. A comparison of the total strain energy release rate with a classical...

..., the total strain energy release rate, and the strain energy release rate components. The parameters controlling the behavior are identified. The effect of specimen stacking sequence and delamination interface on the strain energy release rate components is investigated. Results are compared with a finite...

...MS El-Zein; KL Reifsnider An equation for the strain energy release rate G 1 of a double cantilever beam (DCB) specimen for an anisotropic material is obtained. Results show that for an orthotropic material, the solution coincides with the isotropic one. However, for a more general anisotropic case...

... strain-energy release-rate Glc was calculated from GIc = P ~ / 2 B d C / da where P~ = critical load for crack extension, B = specimen width, C = compliance, and a = crack length. Further details about analysis of DCB data are presented in Ref 3. Results and Discussion The results from the three T6C...

...TK O'Brien; IS Raju; DP Garber A laminated plate theory analysis is developed to calculate the strain energy release rate associated with edge delamination growth in a composite laminate. The analysis includes the contribution of residual thermal and moisture stresses to the strain energy released...