Experimental study on compressive strength of fly ash grouting material

Based on the industrial application of fly ash, a new method of using fly ash instead of sand as the main raw material for wall grouting of coal mine roadway is proposed. The effect of fly ash instead of sand on the compressive strength of shotcrete was studied, and the activation of fly ash shotcrete with Na₂SO₄, NaOH and Na₂SiO₃ were studied. The results show that the compressive strength of the grouting material is lower than that of the traditional grouting material when the fly ash completely replaces the sand, which can not meet the requirement of field application, the problem of compressive strength of fly ash shotcrete can be effectively solved by adding proper amount of alkaline activator, and when the content of Na₂SO₄ is 3%, the increase of compressive strength of fly ash shotcrete is the best.