Experimental Study Of Laminated Composite Tubes Under Bending

Bending stiffness of laminated composite tubes was determined experimentally using four-point bending test. The experimental results were compared with the results obtained by the laminated plate and smear property approaches. The results indicate that experimental values are closer to prediction of the laminated plate approach compared to smear property approach. Effects of tube radius and stacking sequence and fiber orientation of the walled thickness laminate on bending stiffness and strength of composite tubes were studied. Fracture analysis was conducted to investigate the failure process of the tube. Both techniques of x-ray radiography and optical microscopy were used in this study. It is found that damage is initiated at the loading point. The failure process depends on the fiber orientation and ply stacking sequence of the walled laminate of the tubes. The tubes finally failed in compression. Fiber breakage and delamination were observed as the prominent damage modes.