硅酸钠对电石渣/矿渣复合胶凝材料性能影响

Effect of Sodium Silicate on the Properties of Carbide Slag and Blast Furnace Slag Composite Cementitious Materials

电石渣激发效果有限,需复配其他活性激发剂使用,本试验研究了硅酸钠对电石渣/矿渣复合胶凝材料水固比、凝结时间和抗压强度的影响,并结合X射线衍射(XRD)仪、扫描电镜(SEM)等对复合胶凝材料的水化产物和微观形貌进行分析。结果表明,随着硅酸钠掺量增加,电石渣/矿渣复合胶凝材料的水固比增加,凝结时间缩短,抗压强度呈现先升高后降低的趋势,当硅酸钠掺量为0.5%时,其抗压强度最高。微观分析发现,在硅酸钠掺量为0.5%时,试件硬化体的水化硅(铝)酸钙(C-(A)-S-H)和钙矾石(AFt)衍射峰强度增加,未水化的Ca(OH)_(2)含量降低,结构致密,从而使强度得到提高。

The activation effect of carbide slag is limited,it needs to be mixed with other activators for use.The effect of sodium silicate on the water solid ratio,setting time,and compressive strength of calcium carbide slag/blast furnace slag composite cementitious material was studied,and the hydration products and microstructure of the composite cementitious material were explored using micro testing techniques such as XRD and SEM.The results showed that with the increase of sodium silicate content,the water solid ratio of carbide slag/blast furnace slag composite cementitious material increased,the setting time shortened,and the compressive strength showed a trend of first increasing and then decreasing.When the sodium silicate content was 0.5%,its compressive strength was the highest.Microscopic analysis found that when the sodium silicate content was 0.5%,the C-(A)-S-H and AFt diffraction peaks of the hardened body of the specimen increased,while the content of unhydrated Ca(OH)_(2)decreased,resulting in a dense structure and improved its strength.