粉煤灰和矿渣掺量对混凝土组成、结构和性能的影响

Influence of fly ash and slag content on composition, structure and performance of concrete

对粉煤灰和矿渣掺量对混凝土的组成、结构和性能的影响采用SEM、TD-DTA、压汞法和加速碳化试验法等进行了研究。硅酸盐水泥数量是影响浆体中孔径≥10nm孔隙率的决定性因素。硅酸盐水泥数量和矿渣与粉煤灰的质量比是影响孔径≥100nm孔隙率的重要因素。混凝土抗压强度与孔径≥20nm孔隙率之间存在最大的相关性。掺粉煤灰和矿渣混凝土的抗碳化性能主要取决于硅酸盐水泥数量。当粉煤灰和矿渣总掺量固定时,混凝土抗碳化性能与孔径≥100nm孔隙率密切相关。

The effects of the content of fly ash and slag on composition, structure and performance of concrete are studied. Some test methods such as SEM, TD-DTA, mercury intrusion method and accelerated carbonation are adopted. The amount of Portland cement is the decisive factor to affect the porosity of pore size ≥ 10 nm. Both the amount of Portland cement and the mass ratio of slag to fly ash are important factors that affect the porosity of pore size ≥100 nm. The greatest correlation is shown between concrete compressive strength and porosity of pore size ≥20 nm. The carbonation resistance of concrete with slag and fly ash mainly depends on the amount of Portland cement. When the total amount of slag and fly ash is fixed, the carbonation resistance of concrete is closely related to the porosity of pore size ≥ 100 nm.