赤泥-陈积粉煤灰加气混凝土配合比优化试验研究

Research on optimization test of red mud-fly ash aerated concrete mix

为大量使用工业废弃物赤泥,在陈积粉煤灰加气混凝土的基础上,探讨赤泥掺量对陈积粉煤灰加气混凝土力学性能及耐久性的影响。结果显示:赤泥掺入后,会降低陈积粉煤灰加气混凝土的流动性、抗压强度、抗冻性能和干燥收缩,会增加陈积粉煤灰加气混凝土的干密度,会使陈积粉煤灰加气混凝土的气孔结构多成扁平状态和连通状态,进而降低陈积粉煤灰加气混凝土的力学性能;通过对陈积粉煤灰加气混凝土流动性的改善(粉煤灰浆∶赤泥浆∶生石灰∶水泥∶铝浆=1875∶625∶245∶185∶18.3),减水剂掺量为0.02%,铝粉搅拌时间为35 s,粉料搅拌时间为180 s,浇注温度为46~47℃,赤泥-陈积粉煤灰混凝土加气混凝土满足A3.5B06的要求。结论:赤泥浆可替代陈积粉煤灰浆制备加气混凝土(即大量使用陈积粉煤灰的同时也可使用一定量的赤泥),有利于降低加气混凝土的成本。

In order to use a large number of industrial waste red mud,based on fly ash aerated concrete,this paper discusses the influence of red mud content on the mechanical properties and durability of fly ash aerated concrete.The test results show that:after adding red mud,the fluidity,compressive strength,frost resistance and drying shrinkage of fly ash aerated concrete will be reduced,but the dry density of fly ash aerated concrete will be increased.At the same time,it will make the pore structure of fly ash aerated concrete flat and connected,and then reduce the mechanical properties of fly ash aerated concrete.After improving the fluidity of fly ash aerated concrete,that is:fly ash slurry:red mud:quicklime:cement:aluminum slurry=1875∶625∶245∶185∶18.3,water reducing agent dosage is 0.02%,aluminum powder mixing time is 35 s,powder mixing time is 180 s,pouring temperature is 46~47℃,red mud-fly ash aerated concrete meets requirements of A3.5B06.Therefore,red mud can be used to replace the fly ash slurry to prepare aerated concrete,that is to say,a large amount of fly ash and a certain amount of red mud can be used to reduce the cost of aerated concrete.