激发材料对碱性钢渣替代水泥早期强度规律研究

Study on the Early Strength Law of Alkaline Steel Slag Replacing Cement by Chemical Excitation

以碱性钢渣为研究对象,在机械粉磨基础上,采用化学激发方式探究碱性钢渣替代水泥早期强度变化规律;研究不同种类、掺量化学激发剂对钢渣活性的作用,利用XRD、SEM对钢渣替代水泥的水化产物进行分析。结果表明:机械粉磨能够有效改善钢渣粒径中的粗颗粒和细颗粒含量,优化颗粒级配,最佳粉磨时间为20 min;化学激发能够在机械粉磨上进一步提高钢渣胶凝活性,当早强剂掺量为2.0%、芒硝掺量为3.0%、氢氧化钠掺量为1.0%、钢渣掺量为25%时效果最佳;钢渣替代水泥主要水化产物是方解石(CaCO_(3))、氢氧钙石(Ca(OH)_(2))、硅酸二钙(Ca_(2)SiO_(4))和C-S-H凝胶,微观组织呈现纤维网状结构,为力学性能的提高奠定了基础。

Alkaline steel slag as the research object,the change law of alkaline steel slag cementitious activity was investigated by chemical excitation methods.The effects of different kinds and dosage of chemical activators on the activity of steel slag were studied.Hydration products of cement replaced by steel slag were analyzed by XRD and SEM.The results show that mechanical grinding can effectively improve the content of coarse and fine particles in the steel slag particle size,and optimize the particle gradation.The optimal grinding time is 20 min Ininters Chemical excitation can further improve the cementitious activity of steel slag on the basis of mechanical stimulation,and the best effect is obtained when the self-made early-strengthening agent dosing is 2.0%,the dosage of mirabilite is 3.0%,the dosage of sodium hydroxide is 1.0%,and the dosage of steel slag is 25%.The main hydration products of cement replaced by steel slag are calcite(CaCO_(3)),calcium hydroxide(Ca(OH)_(2)),dicalcium silicate(Ca_(2)SiO_(4)),and C-S-H gel.The microstructure presents a fiber network structure,which lays the foundation for the improvement of mechanical properties.