机制砂特性对C80混凝土工作性的影响

Influence of Manufactured Sand Properties on Workability of C80 Concrete

为了研究机制砂对高强混凝土工作性的影响,探讨了石粉质量分数、母岩特性、级配和颗粒形状等因素对C80混凝土工作性的作用.结果表明:由石灰岩、云母岩和铁尾矿3种母岩机制砂制备的C80混凝土的坍落度和扩展度大小按石灰岩>云母岩>铁尾矿的顺序排列;质量分数为3%~6%石粉的机制砂对C80混凝土的工作性有利;当MB值为0.5 g/kg时,新拌C80混凝土的工作性最好;圆形度大于0.87的机制砂可以用来制备出与使用河砂工作性相同的C80混凝土.

To explore the influence of manufactured sand on the workability of high-strength concrete,this paper discussed the characteristics of different mother rocks,stone powder content,gradation,and particle shapes.The results show that the slump and expansion of C80 concrete mixed with limestone,mica rock,and iron tailings are arranged in the order of lime-stone>mica>iron tailings;the workability of C80 concrete can be improved when the content of limestone powder in manufactured sand is 3%~6%;when the MB value is 0.5 g/kg,the workability of fresh C80 concrete is the best;the manufactured sand with roundness greater than 0.87 can be used to prepare C80 concrete with the same workability as river sand.