Experimental study on compressive buckling behavior of J-stiffened composite panels

Abstract Fringe projection profilometry was used to study compressive buckling behavior of composite panels stiffened by J-shaped ribs. The basic principles of dynamic four-step phase shifting technique and multi-frequency unwrapping method in the fringe projection profilometry are introduced. These techniques were used to monitor the morphological changes of the composite panel under in-plane compression. At the same time, strain gauges were utilized to monitor strain history at each point on the surface of the panel. Optical measurement shows the full-field buckling deflection and buckling mode at different moments, and it produces richer data than strain gauges. The experimental results show that the local buckling increases with the loading until the ribs are unstable, which is verified by the finite element calculations.