COMPARATIVE STUDIES ON CUTOUT ZONE REINFORCEMENGT OF COMPOSITE REAR PRESSURE BULKHEAD

To study the influence of the pattern of opening reinforcement on fuselage rear pressure bulkheads, a series of biaxial tensile tests of satin-carbon fabric/epoxy composites reinforced using different opening reinforcement processes were carried out. Based on the test conditions, a finite element model was established. The effectiveness and differences of two reinforcing methods were discussed. The experimental and simulation results show that the strains of each ply are symmetrical to the current ply fiber direction under biaxial tensile loading. In cruciform specimens, both composite stiffening rings and metal stiffening rings can improve the strength of the specimen with large opening effectively. By analyzing strain distribution around the hole, it can be concluded that the composite material reinforcement is more effective, for the maximum strain value is comparatively small and it has better manufacturing properties. The simulation results agreed well with the experimental results, which confirmed that this simulation method can be used in the further evaluation of full scale rear pressure bulkhead performance.