CONSTRUCTION MIXTURE FOR MAKING ROOFING SHEET AND METHOD OF MAKING ROOFING SHEET Russian patent published in 2013 - IPC C04B28/04 B28B1/08 C04B111/20 

FIELD: chemistry.

SUBSTANCE: invention relates to construction industry and specifically to making a roofing sheet. The construction mixture for making a roofing sheet contains binder - M 500 cement, an aggregate, complex additive Relamix Type 2, gypsum and rock sand. The mixture further contains an antifreeze additive - calcium chloride, and clay as binder, and the rock sand is wastes from beneficiation of iron ore of the following composition, wt %: SiO₂ - 34.1-39.9; Al₂O₃+TiO₂ - 9.8-11.0; FeO+Fe₂O₃ - 12.8-26.1; CaO - 11.3-13.7; MgO - 4.2-5.7; MnO - 0.3-0.55; P₂O₅ - 0.5-0.6; SO₃ - 1.7-3.2; Na₂O+K₂O - 1.3-3.2; loss on ignition - 8.5-15.0, containing 20-30% garnet minerals. The aggregate used is mineral wool and the gypsum used is gypsum dihydrate, with the following ratio of components, wt %: M 500 cement - 25-35, mineral wool - 9-15, clay - 8-12, complex additive Relamix Type 2 - 0.2-0.4, calcium chloride - 1-2; gypsum dihydrate - 3-4; rock sand - wastes from iron ore beneficiation - the balance. The method of making a roofing sheet involves tempering a construction mixture for making a roofing sheet to a free-running mass, depositing a layer of the obtained mortar into a mould and laying a mesh reinforcement made form high-strength fibres, on top of which a second layer of the mortar is placed. The concrete is packed by vibration compaction and treated with ultrasound with frequency of 15-30 kHz for 10-15 minutes, and then dried to solidification.

EFFECT: high quality of the roofing sheet and high frost resistance.

2 cl, 1 tbl, 1 ex