What is the general approach to determine delamination tendency in a laminated plate under load?

What is the general approach to determine delamination tendency in a laminated plate under load?

• A. Visual inspection only.
• B. Measuring only the laminate's weight.
• C. Using fracture mechanics concepts, computing G and comparing to critical values (G_IC, G_IIC) to predict delamination growth.
• D. Ignoring interlaminar properties.

Answer: (C)

Delamination tendency under load is determined by fracture mechanics. An interlaminar crack grows when the energy available for crack extension exceeds the material’s resistance to fracture. The key quantity is the energy release rate, G, which measures the driving force for delamination. For a laminated plate, you assess G for the given loading and geometry and compare it to the interlaminar fracture toughness values, G_IC for mode I (opening) and G_IIC for mode II (sliding). If the calculated G reaches or exceeds these critical values, delamination growth is predicted; if it stays below, propagation is unlikely. In practice, you obtain G using fracture mechanics methods such as the virtual crack closure technique, J-integral, or cohesive-zone modeling, which connect the load, geometry, and material resistance in a quantitative way. This approach captures how interlaminar properties control delamination and why it occurs, something purely visual checks or simple weight measurements cannot reveal.

Delamination tendency under load is determined by fracture mechanics. An interlaminar crack grows when the energy available for crack extension exceeds the material’s resistance to fracture. The key quantity is the energy release rate, G, which measures the driving force for delamination. For a laminated plate, you assess G for the given loading and geometry and compare it to the interlaminar fracture toughness values, G_IC for mode I (opening) and G_IIC for mode II (sliding). If the calculated G reaches or exceeds these critical values, delamination growth is predicted; if it stays below, propagation is unlikely. In practice, you obtain G using fracture mechanics methods such as the virtual crack closure technique, J-integral, or cohesive-zone modeling, which connect the load, geometry, and material resistance in a quantitative way. This approach captures how interlaminar properties control delamination and why it occurs, something purely visual checks or simple weight measurements cannot reveal.