免烧煤矸石粒径对泡沫混凝土性能的影响

EFFECT OF GRAIN SIZE OF UNCALCINED COAL GANGUE ON FOAM CONCRETE

为考察免烧煤矸石粒径对泡沫混凝土基本力学性能和吸水性能的影响,对掺入0.16~0.6 mm、0.6~2.5 mm和2.5~5 mm 3种粒径等级的免烧煤矸石的泡沫混凝土进行了研究,煤矸石的掺量分别为10%、20%和30%,泡沫混凝土的设计密度分别为700 kg/m~3和850 kg/m^(3)。试验结果表明,泡沫混凝土的密度为700 kg/m^(3),抗压强度随着煤矸石掺量有显著的变化;泡沫混凝土的密度为850 kg/m^(3),抗压强度和抗折强度均随着煤矸石掺量的增加而降低,随着煤矸石粒径的增大而降低。煤矸石(0.16~0.6 mm)泡沫混凝土的吸水率较低,煤矸石(0.6~2.5 mm或2.5~5 mm)泡沫混凝土的吸水率较高。煤矸石泡沫混凝土0.16~0.6 mm软化系数随着煤矸石粒径的增大而减小。

The effect of coal gangue grain size on strength of coal gangue foam concrete was studied in this work. Coal gangue was crushed into three grades which were 0.16~0.6 mm, 0.6~2.5 mm and 2.5~5 mm. The compressive, flexural strength water absorption and softening coefficient of coal gangue foam concrete were tested. Coal gangue content is from 10 % to 30 %, and design density of concretes were 700 kg/m^(3) and 850 kg/m~3. The results show the strength of uncalcined coal gangue foam concrete is not lower than those of calcined coal gangue foam concrete reported in the literatures. The compressive strength does not decrease with coal gangue in 700 kg/m^(3) concrete, but compressive and flexural strength decrease with increase of content and grain size in 850 kg/m^(3) concrete. In coal gangue foam concrete with 0.16~0.6 mm, water absorption rate is low, and water absorption rate is high in coal gangue foam concrete with 0.6~2.5 mm or 2.5~5 mm. Softening coefficient of foam concrete exhibits a monotonic decreasing while coal gangue grain size increases.