Protective coating material for inhibiting plastic shrinkage of 3D printing concrete as well as preparation method and forming method of protective coating material

The invention discloses a protective coating material for inhibiting plastic shrinkage of 3D printing concrete as well as a preparation method and a forming method of the protective coating material. The protective coating material for inhibiting the plastic shrinkage of the 3D printing concrete is mainly obtained by stirring and mixing the following components in parts by weight in a dark environment: 30 to 55 parts of a UV resin photosensitive prepolymer, 25 to 40 parts of a UV resin reactive diluent, 1.0 to 2.0 parts of a UV resin viscosity modifier, 1.0 to 2.0 parts of a UV resin photoinitiator and 0.05 to 1.0 part of a functional modification auxiliary agent. A high-pressure uniform spraying and 3D printing integrated process is adopted, a protective coating material is uniformly sprayed on the surface of a 3D printing concrete member while the 3D printing concrete member is formed, a high-performance protective coating is rapidly formed after ultraviolet irradiation, the early-stage plastic shrinkage va