The paper tensile experiment and FEA methods were used to study the damage propagation and failure properties of stiffened composite panels with discrete-source damage.The research results indicate that a notched composite panel is suitable to simulate the discrete-source damage of the stiffened composite panels with discrete-source damage,and there is high strain concentration at the notch end.Break-through of the stringer made the load path changed.Based on the Hashin failure criterion,the FEA method with progressive failure procedure can be used to simulate the notched stiffened composite panels' damage progression and failure procedure effectively.The analytical results have a good correlation with the experimental data.

Experimental and FEA methods are used to study the damage propagation and failure properties of stiffened composite panels with discrete-source damage. Influence of discrete-source damage on residual strength of composite panel is also investigated. The research indicates that the notched composite panel is suitable to simulate the discrete-source damage of stiffened composite panel with discrete-source damage. And there is high strain concentration at the notch end. The break-through of the stringer make the load path changed. The discrete-source damage reduces the compression strength of composite panel by almost 60%. Based on Hashin failure criterion, the FEA method with progressive failure procedure simulates the notched stiffened composite panel’s damage progression and failure procedure effectively. The analytical results have a good correlation with the experimental data.