粉煤灰基地质聚合物/水泥复合材料的力学性能

Mechanical Properties of Fly Ash-based Geopolymer/Cement Composites

以粉煤灰和水玻璃粉体为原料制备地质聚合物干粉材料,研究不同粉煤灰基地质聚合物干粉掺量对粉煤灰基地质聚合物/水泥复合材料力学性能的影响,通过XRD和SEM分析粉煤灰和粉煤灰基地质聚合物/水泥复合材料的物相组成和微观结构。结果表明,粉煤灰基地质聚合物干粉掺量从0增加到60%,复合材料的抗折强度和抗压强度减少,折压比增加,主要是因为粉煤灰基地质聚合物常温下反应时间长,随着粉煤灰基地质聚合物干粉掺量的增加,反应产物中地质聚合物凝胶比例增加,90d后试样的折压比增加。

Fly ash-based geopolymer powders were synthesized by mixing fly ash and water glass powders.The effects of the content of fly ash-based geopolymer powders on mechanical properties of composites were studied.The phase compositions and microstructures of fly ash and fly ash-based geopolymer/cement composites were investigated by XRD and SEM.The experimental results show that the flexural strength and compressive strength of composites decrease,the flexural strength to compressive strength ratio increases,when the content of fly ash-based geopolymer powders increases from 0to 60%.The reaction time of fly ash-based geopolymer is longer at room temperature.The ratio of geopolymer gel increases,when the content of fly ash-based geopolymer powder increases,therefore the flexural strength to compressive strength ratio increases after the samples were cured for 90 d.