基于球形度比的精品机制砂粒形特征研究

机制砂颗粒粒形特征是影响混凝土性能的重要因素。提出了“球形度比”的概念,对精品机制砂的粒形控制指标特征进行了评价。精品机制砂生产工艺中的关键设备主要包括除尘设备和整形设备。精品机制砂的质量特征主要包括粒形良好、有效控制石粉含量和细度模数等。精品机制砂的粒形宜采用球形度比0.8及球形度比0.7两个指标同时控制,1类砂和2类砂均可用于混凝土,3类砂仅用于砂浆。结果表明:采用球形度比来表征精品机制砂的粒形特征是比较合理的,健全了精品机制砂的技术评价体系和检测方法,为推广精品机制砂的规模化生产和应用具有借鉴作用。

Research on the Shape Characteristics of Fine Machine-made Sand Based on Sphericity Ratio

The particle shape characteristics of machine-made sand are important factors affecting the performance of concrete.The concept of“sphericity ratio”is proposed in this paper,and the characteristics of grain shape control indices of fine machine-made sand are evaluated.The key equipments in the production process of fine machine-made sand mainly include dust-removing equipment and shaping equipment.The quality characteristics of fine machine-made sand mainly include good grain shape,effective control of stone powder content and fineness modulus,etc.The particle shape of fine machine-made sand should be controlled by two technical indices of sphericity ratio 0.8 and sphericity ratio 0.7.Class 1 sand and class 2 sand can be used for concrete and class 3 sand is only used for mortar.The results show that it is reasonable to use the sphericity ratio to characterize the grain shape characteristics of fine machine-made sand.The technical evaluation system and detection method of fine machine-made sand have been improved,which may provide guideline for the large-scale production and application of fine machine-made sand.