高钙灰复合矿物掺合料混凝土性能的研究

Research on High-lime Fly Ash Admixture's Effectiveness to Concrete's Properties

以消除高钙灰安定性不良,提高其使用率为目的,从工作性、力学性能和抗氯离子渗透性能等方面,研究了经过改性后的高钙粉煤灰对高性能混凝土各项性能的影响;研究表明,与基准混凝土相比,掺入30%改性高钙粉煤灰后,混凝土30 d抗压强度降低了7.2%,但90 d抗压强度达到甚至超过基准混凝土;改性后的高钙粉煤灰能有效地改善高性能混凝土新拌合物的工作性,初始塌落度提高了30.8%;同时对于抗氯离子渗透性能,28 d氯离子渗透系数降低了50.8%;当与自主研制的AST改性剂复掺时,效果更为明显。

This article takes eliminating the bad stability of HFA, enhances its utilization ratio as the goal, researches the impact of modified high-lime fly ash to the performance of workability,mechanical properties and resistance to chloride ion perme-ability. The results show that comparing to the normal concrete, after adding 30 % modified high-lime fly ash, although the 30 d compressive strength decreased 7.2 %, the 90 d compressive strength exceed normal concrete. The modified high-lime fly ash can improve the workability of new high performance concrete, the slump increases 30.8%. At the same time, the 28 d penetration of chloride ions coefficient decreases 50.8 %. When adding the self-developed AST hi-activity modifier, the effect is more obvious.