A modified model for simulation of mode I delamination growth in laminated composite materials

• A modified model has been proposed for simulation of mode I delamination growth in laminated composite materials.
• An analytical equation based on the energy approach has been proposed for extraction of mode I delamination R-curve.
• The new proposed model along with the extracted R-curve considers the fracture process zone effects.
• A comparison of the extracted R-curve with available experimental data shows the capabilities of the proposed method.

In this paper, a modified model has been proposed for simulation of mode I delamination growth in laminated composite materials. The proposed model called “multi-linear cohesive zone model” utilizes spring elements to consider the residual strength of the damaged material in the fracture process zone. As the crack propagates, stiffness characteristics of spring elements change gradually according to the traction-separation curve. In this model, unlike the previous ones, all possible softening behaviors of the traction-separation curve, even nonlinear behavior, could be taken into account. An analytical equation based on the energy approach has also been proposed for extraction of mode I delamination R-curve. The multi-linear cohesive zone model along with the R-curve extracted by the model considers the fracture process zone effects. A comparison of the R-curve obtained by the new model with the available experimental data shows the capabilities of the proposed method.