煤矸石粗骨料对混凝土力学性能的影响

Study on physical and chemical properties and mechanical properties of gangue coarse aggregate

针对煤矿煤矸石产量大、利用率低等问题,对煤矸石作为混凝土骨料的理化性能和力学性能进行了探究。试验结果表明:与普通碎石相比,非自燃煤矸石的堆积密度与表观密度小、吸水率高、压碎值大,当水灰比不变时,煤矸石混凝土的强度随着煤矸石粗骨料掺量的增加先增加后减小;当非自燃煤矸石混凝土掺量不变时,煤矸石混凝土的强度随着水灰比的增加先增加后减小。水胶比为0.5,煤矸石粗骨料取代率为40%时,煤矸石混凝土的强度最高为最优配合比。煤矸石可以作为混凝土粗骨料使用,但若全部采用煤矸石作为混凝土粗骨料,应限制煤矸石粗骨料在强度要求较高的混凝土中使用。

Aiming at the problems of large output and low utilization rate of coal gangue in coal mine,the physical and chemical properties and mechanical properties of coal gangue as concrete aggregate were studied.The experimental results show that,compared with common gravel,the bulk density and apparent density of non-spontaneous coal gangue are smaller,the water absorption rate is higher,and the crushing value is larger.When the water-cement ratio remains unchanged,the strength of coal gangue concrete first increases and then decreases with the increase of the coarse aggregate content of coal gangue.When the content of non-spontaneous coal gangue concrete is constant,the strength of coal gangue concrete increases first and then decreases with the increase of water-cement ratio.Water cement ratio is0.5,gangue coarse aggregate replacement ratio was 40%,the strength of the coal gangue concrete optimal mixture ratio is the highest.Coal gangue can be used as concrete coarse aggregate,but if all coal gangue is used as concrete coarse aggregate,the use of coal gangue coarse aggregate in concrete with higher strength requirements should be restricted.