Application test of coal gangue-based concrete in underground roadway hardening engineering

Coal gangue is one of the larger solid wastes in China at present.It is one of the efficient ways to use coal gangue to produce coal gangue-based concrete instead of concrete coarse aggregate.Through the laboratory tests on the compressive strength of coal gangue-based concrete under different conditions of coal gangue coarse aggregate substitution ratio, water-binder ratio and additives, this paper probes into the basic mechanical properties of coal gangue-based concrete, the optimum mix ratio of coal gangue-based concrete is determined.The results show that the compressive strength of coal gangue-based concrete decreases with the increase of coal gangue coarse aggregate substitution ratio; the addition of 5% silica fume and 0.3% water reducer is helpful to rapidly improve the early strength of coal gangue-based concrete.On this basis, the underground hardening test of coal gangue-based concrete is carried out in the rubber 5^# auxiliary roadway in No.2 mining area of Licun Coal Mine in Shanxi Province, and the good effect of coal gangue-based concrete in underground hardening engineering is verified.