尾矿砂商品混凝土的试验研究与工程应用

用细度模数为1.8的铁矿尾矿砂,分别以30%,40%,50%和60%的比率取代天然砂,配制C20,C30和C40商品混凝土。通过与基准混凝土的对比试验,研究了不同取代率时,尾矿砂混凝土的和易性、抗压强度等性能以及50%取代率时,尾矿砂混凝土抗氯离子渗透性能。结果表明：尾矿砂取代率为30%,40%和50%时,各强度等级的尾矿砂混凝土的和易性、抗压强度均能满足要求;当取代率达到60%时,混凝土和易性较差,但抗压强度仍能满足要求;当取代率为50%时,尾矿砂混凝土抗氯离子渗透能力与基准混凝土相当。将尾矿砂取代率为40%和50%的混凝土应用于相关工程,经持续质量跟踪,未发现任何问题,且经济和社会效益显著。

Experiment Research and Engineering Application of Commercial Concrete from Ore Tailings Sand

Using ore railings sand （OTS） with fineness module of 1.8 in a ratio of 30%, 40%, 50% or 60% to substitute natural sands, commercial concretes with strength grades of C20, C30 and C40 were prepared. Through the contrast experiment of the normal concrete, the properties like workability, compression strength of OTS-based concrete with different substitution ratios and anti-permeability from chloride ion of OTS-based concrete with 50% substitution ratio were studied. The results indicate that these OTS-based concrete can meet the requirements in terms of workability and compression strength with substitution ratio of 30%, 40%, and 50%. With substitution ratio at 60%, its workability is relatively poor while its compression strength still meets the requirement. With substitution ratio at 50%, the OTS-based concrete has similar anti-permeability from chloride ion to normal concrete. With continuous quality monitoring, the OTS-based concrete with substitution ratio at 40% and 50%, which was applied to some projects, does not raise any problem and has significant economic and social benefits.