Method for improving crack resistance of recycled concrete

A method for improving the crack resistance of recycled concrete, which relates to the technical field of concrete. In this method, slag powder, anti-crack composite fiber and silica fume are added into recycled concrete to prepare anti-crack recycled concrete to improve the anti-crack performance. The anti-crack recycled concrete comprises the following components in parts by weight: 200-250 parts of cement, 150-200 parts of water, 550-650 parts of recycled coarse aggregate, 500-600 parts of recycled fine aggregate, 40-70 parts of slag powder, 80-100 parts of anti-crack composite fiber and 4-8 parts of silica fume. According to the invention, the slag powder, the anti-crack composite fiber and the silica fume are added into the recycled concrete to prepare the anti-crack recycled concrete, so as to improve the anti-crack performance of the recycled concrete, and the compressive strength is up to 59.6MPa and the splitting tensile strength is up to 5.3MPa.