硅酸钠模数对高粉煤灰掺量地质聚合物力学性能的影响

Effect of Sodium Silicate Modulus on Mechanical Properties of Geopolymers with High Fly Ash Content

摘要: 研究了模数0.3至1.8 M范围内的硅酸钠溶液对粉煤灰掺量高达90%的粉煤灰基地质聚合物力学性能的影响。结果表明：常温养护条件下，高粉煤灰掺量的地质聚合物强度增幅良好，28天抗折强度相对于3天强度增幅为59.6%至130.2%，28天抗压强度相对于3天强度增幅范围达到123.2%至161.9%。抗压强度随龄期增幅总体高于抗折强度。对于粉煤灰掺量90%的地质聚合物胶凝浆体，硅酸钠模数对强度影响效果显著，综合考虑3天和28天抗压、抗折强度，硅酸钠溶液模数最优值为1.5 M。

Abstract: The effect of sodium silicate solution with a modulus of 0.3 to 1.8 M on the mechanical properties of fly ash-based geopolymer with a fly ash content of up to 90% was studied. The results show that the strength of geopolymer with high fly ash content increases well under normal temperature curing conditions, and the 28-day flexural strength increases from 59.6% to 130.2% compared to the 3-day strength. The 28-day compressive strength increased from 123.2% to 161.9% compared to the 3-day strength. The increase of compressive strength with curing age is generally higher than that of flexural strength. For geopolymer with a fly ash content of 90%, the modulus of sodium silicate has a significant effect on strength. Considering the 3- and 28-day compressive and flexural strengths, the optimal modulus of sodium silicate solution is 1.5 M.