Method for preparing building material by using phosphogypsum

The invention relates to a method for preparing a building material by using phosphogypsum. The method comprises the steps of firstly, preparing a dry blend by using the phosphogypsum, aluminosilicate industrial residues, a calcium cementing material and aggregate, then adding water or water with a dissolved activator to obtain a wet mixture, standing, carrying out static pressure molding, and finally, carrying out natural or steam curing to obtain an ultrahigh strength material. The method solves the problems that the phosphogypsum has more impurities and is difficult to utilize, and can be used for preparing the ultrahigh strength building material with high compressive strength by enabling the phosphogypsum to be coupled with a great deal of aluminosilicate industrial residues. The ultrahigh strength building material can be used for preparing various high-strength and high-durability products such as high strength building bricks, high strength road bricks, high strength water permeable bricks, road edge