Experimental study on preparing foamed concrete from coal gangue

In order to achieve the high-value added comprehensive utilization of coal gangue,take the gangue as main material,by adding small amount of gypsum,lime and clinker in coal gangue and using aluminum powder as foaming agent preparing foamed concrete.The paper investigated the effect of adding quantity of gangue on bulk density and compressive strength of foamed concrete,and analyzed hydration mechanism and microstructure of foamed concrete by SEM images.The results showed that when the adding ratio of gangue is 66%,the compressive strength is 4.3 MPa and bulk density was 675 kg/m³,and the ettringite and C—S—H gel synergies generated,so the product with better quality.