摘要
将亚硝酸钙掺入硫铝酸盐水泥中,研究其对水泥砂浆流动性、凝结时间、水化历程及砂浆强度的影响规律。试验结果表明:掺加少量亚硝酸钙能提高水泥砂浆的流动性。当其掺量高于1%后,对提高水泥砂浆流动性效果无明显变化;亚硝酸钙能缩短硫铝酸盐水泥水化诱导期,使其直接进入水化加速期,使硫铝酸盐水泥水化放热峰提前约2h,但后期放热速率降低;亚硝酸钙能够提高硫铝酸盐水泥的抗折强度和抗压强度,这是由于亚硝酸钙在促进硫铝酸盐水泥水化产物生成的同时,也能对未水化的水泥矿物起到润滑和分散作用,使其能"逃过"水化胶凝产物的包裹,充分接触水分子,促进水泥完全水化,减少因水泥石中存在未水化矿物而形成的强度薄弱点,从而提高水泥石的强度。
Calcium nitrite was added to sulphoaluminate cement,and its influence on the fluidity, setting time,hydration process and mortar strength of cement mortar was stud- ied. The results show that the addition o{ a small amount of calcium nitrite can improve it go directly into the water acceleration phase, so that the hydrated and exothermic peak of sulphoaluminate cement is about 2 h in advance, but the heat release rate decreases later. The nitrite can significantly improve the flexural strength of the sulphoaluminate cement and compressive strength,which is due to the existence of calcium nitrite in the promotion of hydrated production of sulphoaluminate cement at the same time, but also the unhydrated cement minerals play a role in lubrication, so that it can ＂escape＂ hy- drated rubber,coagulation products of the package,full access to water molecules, the complete hydration of cement is promoted, and the strength of cement stone is reduced due to the presence of non-hydrated mineral weak point, thereby the strength of cement stone is enhanced.
出处
《交通科学与工程》
2017年第4期10-13,共4页
Journal of Transport Science and Engineering
基金
湖南省交通厅科技项目(201605)
关键词
亚硝酸钙
硫铝酸盐水泥
流动性
凝结时间
水化历程
胶砂强度
calcium nitrite
sulphoaluminate cement
fluidity
setting time
hydration process
mortar strength
