NaOH溶液对含铝土矿尾矿加气混凝土性能的影响

Effect of NaOH Solution on the Performance of Aerated Concrete Containing Bauxite Tailings

以NaOH为碱激发剂激发铝土矿尾矿和粉煤灰的活性,采用蒸汽养护方式,制备加气混凝土。研究NaOH添加量和溶液温度对加气混凝土力学性能、干表观密度和导热系数的影响,分析了NaOH添加量和溶液温度对加气混凝土水化特性和微观结构的影响。结果表明,随着NaOH添加量和溶液温度增加,加气混凝土抗压强度均呈先增大后减小趋势;硬化后主要水化产物为CaCO_(3)和托贝莫来石;在NaOH溶液温度为50℃、质量分数为1.0%时,加气混凝土性能达到最佳,抗压强度达到(4.17±0.38)MPa,干表观密度为618 kg/m^(3),干态导热系数为0.1157 W/(m·K)。

Use NaOH as alkali activator to stimulate the activity of bauxite tailings and fly ash,and the aerated concrete was prepared by steam curing steam.The effect of the content of NaOH and solution temperature on the performance of aerated concrete including strength,dry apparent density,thermal conductivity were investigated.The changes of NaOH content and solution temperature on the hydration characteristics and microstructure of aerated concrete were analyzed.The results show that the compressive strength of aerated concrete increases first and then decreases with the increase of NaOH content and solution temperature.The main hydration products after hardening are CaCO_(3) and tobermorite.When NaOH solution mass fraction is 1.0%,at the solution temperature of 50℃,the aerated concrete has the best performance,the compressive strength is(4.17±0.38)MPa,the dry apparent density is 618 kg/m^(3) and the dry thermal conductivity is 0.1157 W/(m·K).