Experimental research on performances of concrete with coal gangue

Coal gangue is a waste from mining coal and it is necessary to use and deal with. It is rarely reported that it is not used by grinding or calcining. Performances of concrete with coal gangue are studied experimentally. The results firstly show that concrete has steady workability when coal gangue takes the place of less than 30% gravel in mass. Apparent density of concrete is increased and mechanical properties increased to a maximum when coal gangue in place of 30% gravel and then decrease. Secondly, Slump of concrete was decreased wholly and mechanical properties increased to a maximum when fly ash takes the place of 20% cement, then decrease. But its apparent density is steady when fly ash is in place of more cement. Thirdly, concrete with coal gangue increases in workability and decreases in mechanical properties when slag takes place of more cement. Lastly, concrete with slag has higher mechanical properties than concrete with fly ash..