Potential application of jet 3D printing technology for crack repair on asphalt pavement

To clarify the key points and direction of injection 3D printing technology for repairing pavement cracks, the types and repair methods of common pavement cracks are summarized, and the characteristics of pavement crack repair methods are introduced, including advantages of the injection method. Two kinds of 3D printing technology, 3D printing main molding technology and the advantages of 3D printing technology for repairing pavement cracks are introduced. Based on injection method and 3D printing technology, the injection 3D printing technology, equipment and 3D printing materials are proposed in this paper. It is summarized as follows. (1) Jet 3D printing technology is used to repair pavement cracks without slotting cracks. Repair material in the nozzle is jetted at a high speed, and the bond strength with crack wall is high, the repair effect is good. (2) Research on the technology of automatically determining the print path after the equipment identifies cracks, so that the equipment can complete the two processes of picture confirmation print path and print head jet repair material at the same time. The efficiency and accuracy of printing cracks are improved. (3) Emulsified asphalt is modified by mineral powder, water-based epoxy resin and styrene-butadiene rubber. Asphalt is modified by rubber, SBS, polyethylene, epoxy resin, etc., or by adding two or more polymers. The materials such as polyurethane and adhesive can be modified by titanium dioxide/shape memory polyurethane composite material and Duct Tape Federation (DTF) self-adhesive suture tape. Our research group intends to use rubber and C₉ petroleum resin to modify SBS modified asphalt. It can obtain a 3D printing asphalt pavement crack repair material with good viscosity, elasticity, high temperature stability and low temperature ductility. (4) Strengthen the research on printability of asphalt, the bonding strength between repair materials and crack edges, and other performance tests. Evaluation indicators should achieve a unified standard.