活化煤矸石改性混凝土的抗氯离子渗透性能

Anti-chloride Ion Diffusion Property of Concrete Modified by Activated Coal Gangue

采用活化煤矸石作为矿物掺合料配制煤矸石混凝土,研究活化煤矸石对混凝土抗氯离子渗透性能的影响。运用机械-热复合活化方式对煤矸石进行活化,采用强度评价法评价活化煤矸石的活性,确定最佳激活条件;利用经最佳激活条件处理的煤矸石按照不同配比制成煤矸石混凝土,采用快速测定法对该混凝土进行抗氯离子性能测试。研究发现:球磨3 h并经800℃煅烧的煤矸石,抗压强度评价系数达到80.9%;经过该条件处理的煤矸石掺量为30%、水胶比为0.4、砂率为0.35时,氯离子扩散系数最小,为6.356 4μm2/s。通过数据拟合得出混凝土氯离子扩散系数同活化煤矸石掺量之间的函数关系,可用以确定一定范围内活化煤矸石掺量对改性混凝土中氯离子扩散系数的影响。

In order to research the effects of activated coal gangue for the concrete anti-chloride ion diffusion property, concrete is prepared by using activated coal gangue as the mineral mixture. Coal gangue is activated by machinery-thermal activation method at first, and then its activity is evaluated to get the best activity condition by activity evaluation method. The coal gangue which is activated by the best activity condition is used to prepare different mixing ratios＇ concrete and testing its anti-chloride ion diffusion property by rapid assessment method （RAM）. The strength evaluation coefficient of activated coal gangue after 3 h milling and 800 ℃ burning can get to 80.9%. The Cl^- diffusion coefficient of as-prepared concrete can reach the minimum value 6.356 4 μm^2/s when the mix ratio of activated coal gangue to raw content is 30%, the water/binder ratio 0.4 and the sand ratio 0.35. The function relation of the Cl^- diffusion coefficient and the volume of activated coal gangue can be obtained by data fitting, and can be applied for determining the impact of activated-coal-gangue mix ratio on the Cl^- diffusion coefficient in modified concrete within a certain range.