Experimental, Numerical Investigation and Optimization of Effect of Adhesive Joint on Flexural Behavior of grid-stiffened Composite Plates

In this research, numerical and experimental investigations were performed to study the effect of the adhesive joint on the fractural behavior of the lattice composite plates. Foam format was designed to construct two samples of lattice composite plates, and the hand layup technique was used to prepare the ribs. Finally, the obtained ribs were connected to the composite shell in the interface of ribs with shell using Axson H9940 BK for first sample and LR520 resin adhesives for second sample. The prepared samples were analyzed using the three-point bending test. For this purpose, a test fixture was designed and constructed. The standard test of the crack release energy in the first and second mode, tensile test, and nol test were performed to evaluate the mechanical properties of the carbon cloth, carbon fibrs, resin, and adhesive. The numerical solution of the problem and comparing the obtained results with experimental data revealed that the Axson adhesive connections can tolerate more force in comparison with resin adhesive connections before structure destruction.