Lightweight foam concrete insulating brick and its manufacturing method

The invention relates to a naturally maintained lightweight foam concrete insulating brick which is made of a lightweight insulating material and needs no sintering, autoclaving, and steam curing, and its manufacturing method. The lightweight foam concrete insulating brick comprises by mass: 35%-45% of fly ash, 5%-16% of aggregates, 8%-15% of cement, 2%-8% of slag, 8%-18% of quicklime powder, 4%-10% of plaster stone powder, 2%-5% of expanded perlite, 0.5%-3% of polystyrene foam, 0.5%-5% of an activator, 2%-5% of an early strength agent, and 15%-20% of water. The aggregates can be zeolite, or basalt tailling slag or an arbitrary combination thereof. The brick of the invention has the advantages of energy saving and environmental protection as well as low cost, and its manufacturing technology free of sintering, autoclaving, and steam curing can effectively reduce original ecological resource consumption. By comprehensive utilization of fly ash and polystyrene material wastes, zeolite, basalt tailling slag part