机制砂颗粒粒形特征及其对砂浆性能的影响

Particle Shape Characteristics of Machine-Made Sand and Its Influence on Mortar Performance

本文通过研究机制砂颗粒粒形及其对砂浆性能的影响,发现机制砂颗粒粒形与机制砂空隙率、松散堆积密度关系显著,棱角性、长宽比、丰满比等形貌参数均能很好地表征颗粒粒形特征,尤其是棱角性指标,与空隙率、粗糙度的相关系数分别达到0.957、0.997。砂浆力学性能方面,机制砂的砂浆抗压、抗折强度均比天然砂高5%以上;砂浆体积变形性能方面,机制砂砂浆各龄期干缩率均比天然砂小4.2%~8.7%。

In this paper, the particle shape of machine-made sand and its influence on mortar performance is studied. The results show that the grain shape of machine-made sand has a significant relationship with void ratio and bulk density of machine-made sand. The shape parameters such as angularity, aspect ratio and fullness ratio can well characterize the grain shape characteristics, especially the angularity index. The correlation coefficients with void ratio and roughness are 0.957 and 0.997 respectively. In terms of mechanical properties of mortar, the compressive strength and flexural strength of machine-made sand mortar are more than 5% higher than that of natural sand;in terms of volume deformation performance of mortar, the dry shrinkage of machine-made sand mortar at all ages is 4.2% ~ 8.7% lower than that of natural sand.