Plastering mortar as well as preparation method and application thereof

The invention provides plastering mortar as well as a preparation method and application thereof. The plastering mortar is mainly prepared from the following raw materials in parts by mass: 140 to 160parts of coal ash, 400 to 500 parts of sand, 180 to 220 parts of Portland cement, 80 to 120 parts of ground calcium carbonate powder, 40 to 60 parts of gypsum powder, 10 to 20 parts of rubber powder,3 to 7 parts of lignocellulose, 1 to 3 parts of starch ether and 30 to 40 parts of glass fiber. The plastering mortar disclosed by the invention is prepared by compatibility of used coal ash, sand prepared by crushing concrete blocks and/or bricks of a construction waste treatment station and other components, so that on one hand, the reutilization of waste resources is improved; on the other hand, the plastering mortar prepared according to the formula ratio and a specific plastering process, provided by the invention, is free of hollowing and cracking and high in stability; and besides, theplastering process of the