In order to improve the macroscopic pore structure deterioration of autoclaved aerated lightweight concrete caused by the excessive admixture of iron tailings sand,the regulating effects of the content of gas-foaming agent(aluminum powder)and the mass ratio of gas-foaming agent and foam stabilizer(hydroxypropyl methyl cellulose)on the macroscopic pore structure of autoclaved aerated lightweight concrete with iron tailings sand and the effects on the compressive strength,bulk density and thermal conductivity of the specimens were studied.The results show that when the mass ratio of gas-foaming agent and foam stabilizer is 1∶5 and the content of gas-foaming agent is 0.09％,the autoclaved aerated lightweight concrete with iron tailings sand has moderate compressive strength and bulk density,which is close to the requirements of strength grade A2.5 and bulk density grade B05 specified in autoclaved aerated concrete block(GB/T 11968-2020).On this basis,further increasing the content of foam stabilizer to the mass ratio of gas-foaming agent and foam stabilizer of 1∶7 can effectively increase the proportion of tiny pores(pore area≤0.5 mm2),improve the uniformity of pores,reduce the interconnection rate of pores,so that the unit volume density of autoclaved aerated lightweight concrete with iron tailings sand can withstand pressure increase by 5.19％,and 6.8％lower thermal conductivity,with more excellent compressive and thermal insulation properties.
关键词
铁尾矿砂/蒸压加气轻质混凝土/稳泡剂/羟丙基甲基纤维素/孔隙结构
Key words
Iron tailings sand/Autoclaved aerated lightweight concrete/Foam stabilizer/Hydroxypropyl methyl cellulose/Pore structure
维普
万方数据