铁尾矿砂对泡沫混凝土力学性质和微观结构的影响  

Effect of iron tailings sand on the mechanical properties and microstructure of foam concrete

作　　者：秦毅[1] QIN Yi(Department of Civil Engineering,Eastern Liaoning University,Dandong 118003,China)

机构地区：[1]辽东学院土木工程系,辽宁丹东118003

出　　处：《中国测试》2022年第6期134-142,共9页China Measurement & Test

基　　金：丹东市住房和城乡建设领域施工技术服务项目(201721060200011)。

摘　　要：采用铁尾矿砂来代替泡沫混凝土中的细骨料,分析不同水灰比、不同铁尾矿砂替代量和不同材料表观密度条件下的铁尾矿泡沫混凝土力学性能的变化规律。结果表明:当铁尾矿替代率为20%时,泡沫混凝土抗压强度和抗折强度均达到最大值;当水灰比在0.40时混凝土的强度达到最大值;而随着表观密度等级的增大,铁尾矿泡沫抗折强度的变化规律呈现稳步增大的趋势,且抗压强度的变化规律则呈现出先快速增大后缓慢增大的趋势。同时,掺加铁尾矿砂和小粒径的铁尾矿的泡沫混凝土可以有效提升泡沫混凝土的抗冻性能。在剪切速率一定时,随着水灰比和铁尾矿替代率的增大,泡沫混凝土剪切应力的变化规律呈现出增大的趋势,表观粘度值的变化规律呈现出减小的趋势。Iron tailings sand is used to replace the fine aggregate in foamed concrete,and the changes in the mechanical properties of iron tailings foamed concrete under different water-cement ratios,different replacement amounts of iron tailings and different material apparent densities are analyzed.The results show that when the replacement rate of iron tailings is 20%,the compressive strength and flexural strength of foam concrete reach the maximum.When the water-cement ratio is 0.40,the strength of concrete reaches its maximum.With the increase of the apparent density grade,the change law of the flexural strength of iron tailings foam shows a steady increase trend.And the change laws of compressive strength presents a trend of rapid increase first and then slowly increase.At the same time,the foamed concrete mixed with iron tailings sand and small particle size iron tailings can effectively improves the frost resistance of the foam concrete.When the shear rate is constant,with the increase of the water-cement ratio and the replacement rate of iron tailings,the shear stress of foamed concrete shows a increasing trend.And the change law of apparent viscosity value shows a decreasing trend.

关 键 词：水灰比 铁尾矿砂替代量 表观密度 抗冻性能 表观粘度 

分 类 号：TD325[矿业工程—矿井建设]