复合矿渣微粉对混凝土抗氯离子侵蚀性能影响的野外试验研究

采用测定混凝土中氯离子显色渗透深度的方法,研究大掺量矿渣微粉混凝土和大掺量复合矿渣微粉混凝土的抗氯离子侵蚀性能,并与纯水泥混凝土进行对比。发现经3年海水浸泡后,在0.36水胶比的混凝土中,用比表面积为400 m2/kg的矿渣微粉取代65%的水泥可降低混凝土氯离子显色渗透深度75%,增加矿渣微粉细度至600 m2/kg或使用复合矿渣微粉均可进一步降低混凝土氯离子显色渗透深度50%左右。结果表明采用大掺量复合矿渣微粉是一种提高混凝土抗氯离子侵蚀能力的有效手段。

Chloride penetration resistance of concrete with multiplex-slag after 3 years of exposure in seawater environment

The chloride penetration resistance of concrete was investigated by measuring the colorimetric chloride penetration depth.The specimens were exposed in seawater environment for 3 years.The concrete types include plain Portland cement concrete,high volume slag concrete with different slag fineness,and high volume multiplex-slag concrete.The water-binder-ratio was 0.36.Test results confirm that concretes containing high volumes of slag or multiplex-slag exhibit improved chloride penetration resistance when compared with plain Portland cement concrete.Using slag with a fineness of 400 m2/kg to replace 65% of cement could decrease the colorimetric chloride penetration depth by as much as 75%,and increasing the fineness of slag to 600 m2/kg or using multiplex-slag could further decrease the colorimetric chloride penetration depth by about 50%.The results indicate that using high volume of multiplex-slag could be an effective method for improving the chloride penetration resistance of concrete.