A method for automatic integration of fiber mesh reinforcement within 3D printed concrete layers

State-of-the-art methods for reinforcement of 3D printed concrete layers require manual intervention, cause poor bonding between concrete and reinforcement, or result in a disrupted concrete flow. This paper presents a method to reinforce printed layers automatically. A novel printhead is developed, which bifurcates the input concrete flow and merges the two channels back near the tapering outlet. The fiber mesh is dragged from a spool housed in the printhead within the layer being printed. Mesh reinforced concrete was printed along linear and curved paths. A greater path radius helped reduce out-of-plane distortion in the mesh (and concrete) along curvilinear paths. Compaction due to tapering in the printhead reduced amount of voids near mesh, and increased green strength and mesh pull out force in fresh state. Further, cubes extracted out of printed beams had strength similar to mould cast cubes. Presence of fiber mesh substantially enhanced the deformability of printed beams.