Add to ORKGABSTRACT: The aim of this study was to explore easy technologies for manufacturing of integral composite structures to evaluate the manufacturing concepts. This has been done by determining the buckling and post-buckling behavior of hat-stiffened composite panels under compression loading. A shadow Moire ́ technique was used to monitor the out-of-plane displacement of the skin panel. The experimental results of hat-stiffened panels for initial buckling and post-buckled response of the panels were compared with numerical results obtained from linear and non-linear finite element methods. It was found to be in reasonably good agreement with each other. The panels showed good post-buckling strength and total failure began with the local buckli...