碱激发矿粉胶凝材料的力学性能及微观研究

Mechanical Properties and Microstructure of Alkali-activated Cementitious Materials from Ground Blast Furnaced Slag

本文利用S95级矿粉作为主要原料制备碱激发胶凝材料,研究了氢氧化钠、水玻璃用量以及水胶比对碱激发矿粉砂浆抗折、抗压强度的影响;利用XRD和SEM等测试方法对碱激发矿粉净浆的反应产物及特征进行分析。结果表明:在矿粉用量为450g、标准砂用量为1350g时,水胶比为0.5,氢氧化钠和水玻璃用量分别为25g和180g,所制备的碱激发矿粉砂浆力学性能最优,其28d抗折强度可达13.7MPa,抗压强度可达120.3MPa。XRD和SEM分析结果表明,碱激发矿粉胶凝材料的结构成分主要为C-S-H胶体和钠长石(Na2.12Al2Si2O8.06)相。

The paper studied the effects of NaOH content,water glass content and w ater-binder ratio on the flexural and compressive strength of the mortars,which alkali-activated cem entitious material with ground blast furnaced slag BFS as a main precursor.The reaction products and their characteristics of alkali-activated material were analyzed by XRD and SEM.The results shows that the optimal mixing ratio of alk aliactivated mortar is NaOH dosage of 25 g,sodium silicate dosage of 180 g and w ater-binder ratio of 0.5,as the contents of BFS and the standard sand is 450 g and 1350 g respectively,the flexural strength and compressive strength at 28 d could reach to 13.7 MPa and 120.3 MPa in the mortars prepared under the optimal condition.XRD and SEM results shows that the structural phases of alkali-activated cementitious material are mainly C-S-H and albite(N a2.12Al2Si2 Og.06)phase.