Experimental Investigation of the Fatigue Behavior Of 3D Printed Steel Fiber Reinforced Concrete

Currently, the development of innovative production methods for concrete structures is progressing rapidly. As an example, the state-of-the art on 3D printing of cementitious materials has progressed from the  pioneering work of printing mortars to printing with conventionally proportioned concretes at structural scale. Recent advances have even enabled printing of concrete reinforced with steel fibers. With the rapid development, including the improvement of material toughness from the addition of fibers, the road is paved for advanced applications, including utilization of 3D printed concrete as the sole load bearing system of larger structures. With increasingly complex structures, an increased need for documentation of material properties at certain load conditions follows. This paper presents an experimental investigation of the fatigue behavior of 3D printed fiber reinforced concrete in compression. The experimental program is to be considered as a preliminary test program, providing indications on the question if the fatigue life of the fiber reinforced 3D printed concrete material can be compared to the fatigue life of conventional concrete, e.g. as predicted by the Eurocode provisions. The results are compared with similar tests on 3D printed concrete without fibers to demonstrate that the inclusion of fibers does not impact the fatigue behavior negatively. From the experiments conducted, it is found that the behavior of the 3D printed materials exposed to fatigue loading, is comparable to the prediction models for fatigue life of conventional concrete.