Synchronous grouting material capable of preventing duct piece from floating upwards and application of synchronous grouting material

The invention discloses a synchronous grouting material capable of preventing a duct piece from floating and a preparation method of the synchronous grouting material, and aims to solve the technical problems that the actual operability of synchronous grout grouting at the present stage is poor, and floating of the duct piece is difficult to control. The synchronous grouting material is prepared from a solution A and a solution B, the solution A comprises cement, sand, fly ash, bentonite and water, and the solution B is an aqueous solution of polyacrylamide with the molecular weight of 8-12 million. The synchronous grouting material prepared by the method is small in volume shrinkage and small in bleeding rate after being solidified, can be obviously and effectively controlled aiming at the problem of floating of duct pieces, and can save a large amount of cost, reduce process conversion, reduce personnel allocation, reduce material types, shorten process time and improve shield tunneling ...