石灰石粉对砂浆耐磨性能的影响及作用机理

Influence of Limestone Powder on Abrasion Resistance of Mortar and Its Mechanism

采用石灰石粉等质量取代河砂和机制砂,研究了石灰石粉掺量(质量分数)对砂浆耐磨性能的影响,并结合显微硬度和扫描电镜(SEM)对其进行了机理分析.结果表明:随着石灰石粉掺量的增大,砂浆耐磨系数先减小,后增大;其中河砂砂浆的最佳石粉掺量为15%;机制砂砂浆的最佳石粉掺量为10%.显微硬度测试结果表明,石灰石粉提高了水泥石的硬度,改善了水泥石与骨料的界面过渡区;SEM表明,石灰石粉加速了C-S-H凝胶的生成,从而使C-S-H在7d时便产生了许多网络状粒子.

Influence of contents of limestone powder（LP）to substitute river sand（RS） and manufactured sand（MS） at equal quantity on abrasion resistance of mortar were studied. The influence mechanism was analyzed by test of micro-hardness and scanning electron microscape（SEM）. Results show that values of abrasion resistance of cement mortar decrease at first, and then increase with the increment of contents of limestone stone. The optimal content of limestone powder in river sand substitution is 15%, the optimal content of limestone powder that to substitute manufactured sand is 10%. Micro-hardness test shows that the hardness of hydrated cement increases and transition zone of cement and aggregate is improved by lime- stone powder. SEM shows that the formation of C-S-H gel is accelerated by limestone powder and many reticular particles of C-S-H may be seen at 7 days.