再生粗骨料砂浆含量测定方法及骨料提升技术研究

Determination of Recycled Coarse Aggregate Mortar Content and Research on Aggregate Lifting Technology

通过煅烧-球磨法测得不同品质再生粗骨料(Ⅰ类、Ⅱ类和Ⅲ类RCA)上的附着砂浆含量,研究了再生粗骨料附着砂浆含量和吸水率的关系;并应用显微硬度计测试再生粗骨料在不同煅烧温度下的硬度损失,在此基础上提出了一种骨料强化的方法。结果表明:Ⅰ类、Ⅱ类和Ⅲ类RCA附着砂浆含量分别为7.48%、22.76%和34.49%,RCA砂浆附着含量、吸水率和压碎指标呈较好的线性关系;RCA的煅烧温度从100℃升到400℃时,显微硬度损失率较小,当煅烧温度达到500℃时,显微硬度损失率达到25.55%。

The attached mortar content of recycled coarse aggregate（ RCA） of different quality（ class I,class II and class III） was measured by calcination ball milling method. The relationship between the content of recycled coarse aggregate mortar and water absorption was studied. The hardness loss of recycled coarse aggregate at different calcination temperatures was tested by micro vickers hardness tester. On the basis of this,a method of aggregate strengthening was put forward. The results show that the content of the attached mortar of class I,class II and class III RCA is 7. 48%,22. 76% and 34. 49%,respectively. There is a good linear relationship between the content of RCA mortar,water absorption and crushing index; when the calcination temperature of RCA increases from 100 ℃ to 400 ℃,the loss rate of micro hardness is smaller. When the calcination temperature reaches 500 ℃,the micro hardness loss rate reaches 25. 55%.