粉煤灰地聚物的力学性能及微观结构研究

研究了在常温、常压养护条件下制备粉煤灰地聚物的工艺,物理力学性能及其水化产物微观结构。结果表明:粉煤灰地聚物在水玻璃模数为1.5,碱固比为0.3,水灰比为0.3时,28d抗压强度为35.9MPa。由FTIR、DTA/TG和超景深显微镜等表征手段推断出:在水化过程中粉煤灰内玻璃体发生了解聚—缩聚反应,即玻璃体被碱溶液溶解解聚后在其边缘发生缩聚反应,生成非结晶相N-A-S-H凝胶,且N-A-S-H凝胶随着时间延长而增加。

Study of the Mechanical Properties and Microstructure of Fly Ash Geopolymer

This paper studied the preparation, mechanical properties and microstructure of hydration products of fly ash geopolymer under normal temperature and curing pressure. The results showed that 35.9MPa compressive strength at 28d can be obtained when fly ash geopolymer with 1.5 water glass modulus, 0.3 alkaline-solid ratio, 0.3 water-cement ratio is prepared. By means of FTIR、 DTA/TG. and super depth field microscope, we can infer that the depolymerization-condensation reaction of vitreous occurs during the hydration of fly ash geopolymer, i.e., the vitreous is dissolved by alkaline solution, then the condensation reaction of its edge occurs so as to produces the non-crystalline phase-N-A-S-H gel, and the N-A-S-H gel increases with the time prolonged.