3D Printed Pseudo-Ductile FRP Composites for Resilient Infrastructure

The use of Fiber Reinforced Polymer (FRP) composites has increased significantly in infrastructure applications due to their superior load-bearing capacity, high specific stiffness, and corrosion-free characteristics. One inherent drawback of FRP composites is their limited ductility, which hinders their widespread use in resilient infrastructure. The ductility of structural elements is required in resilient infrastructure to minimize loss of capacity, ensure appropriate robustness, and maintain structural integrity after extreme events. If FRP can show ductile behavior, it would make an attractive alternative for resilient infrastructure. 3D printing technology offers great potential for manufacturing ductile FRP composites with large freedom in design, high precision, lower material waste, and rapid manufacturing. One major advantage of 3D printing is its precise control of discrete fiber angles. This capability is unavailable when using conventional FRP manufacturing techniques such as vacuum-assisted hand layup. 3D printing offers an unprecedented opportunity to create the next generation of ductile FRP. This paper discusses the use of 3D printing technology in developing pseudo-ductile multi-angle FRP laminated composites. The unique capabilities of 3D printing were utilized to vary fiber orientation angles, the thickness of layers, and stacking sequence to produce several novel designs. The FRP composite designs were evaluated regarding stiffness, strength, and ductility. The results highlight the significance of using low and high fiber angle orientations to obtain proper strength and failure strain and thus maximize ductility. This investigation also introduces a new approach in FRP composite manufacturing by producing mixed fiber-angled composite layers to obtain moderate behavior with respect to layers with discrete fiber orientation. We demonstrate the nonlinear behavior and progressive failure of 3D printed FRP. We also suggest the design of combinatorically angled 3D printed Glass Fiber Reinforced Polymer (GFRP) composites using optimization algorithms to carefully select design parameters such as the fiber angle, stacking sequence, and fiber layer thickness to allow suitable load distribution within the 3D printed FRP composite leading to ductile failure.