钢渣粉硅灰混凝土的力学性能及耐久性研究

Mechanical properties and durability of concrete modified with steel slag and silica fume

通过试验测试分析了钢渣粉单掺以及与硅灰二元复掺混凝土在不同配合比下的和易性、力学性能和耐久性能,并基于改性前后混凝土微观结构特征的测试分析揭示了钢渣粉单掺以及与硅灰二元复掺对混凝土材料的改性机理。试验研究结果表明:钢渣粉取代混凝土中水泥最适宜的比例是10%,此时混凝土的力学性能和耐久性能都得到有效的提高,掺量20%的钢渣混凝土与普通硅酸盐混凝土各项性能相近。钢渣粉与硅灰的二元复掺可以使混凝土的力学性能和耐久性得到显著提高。钢渣粉在混凝土中的作用有两个:一是作为活性胶凝材料发生水化反应,但其活性比水泥低;二是微集料效应,分散水泥颗粒填充混凝土的孔隙,提高混凝土的密实度。

Experimental study was carried out to investigate the physical and mechanical properties ,the durability,and the microstruc-tures of concrete mixed with different percentages of steel slag.At the same time,silica fume was used to improve the performance and the microscopic properties of steel slag concrete.The test results indicate that the steel slag can be used in concrete as cementing material with lower activity than the cement.Steel slag substituting 10%cement by mass improves the mechanical properties and the durability of con-crete.Even up to 20%,the steel slag could be advantageously blended with cement without adversely affecting the performance of concrete. When the mixture uses equal weight portion of steel slag and silica fume ,the strength and the durability of concrete are improved dramati-cally.Steel slag powder has two favorable effects on the concrete performance.Firstly ,steel slag can act as an active cementitious material to improve the hydration reaction in concrete,but its activity is lower than that of cement. Second,Steel slag powder can act as micro-ag-gregate,which disperses the cement particles,fills the pores,and improves the compactness of concrete.