摘要
研究了2个预养护龄期(28和180 d)的硅酸盐水泥和3个矿渣粉掺量(50%、70%和90%)的混合水泥砂浆在加速溶蚀142 d内的溶蚀质量损失规律,分析了硅酸盐水泥和混合水泥初始CaO含量、浆体中氢氧化钙(CH)含量和水化程度,基于浆体中CH含量与水泥初始CaO含量,以及溶蚀质量损失之间的关系,探讨了水泥初始CaO含量与砂浆溶蚀质量损失之间的关联性,并阐述了水泥浆体水化程度对此关联性的影响。结果表明:在溶蚀过程中,2个预养护龄期下的砂浆溶蚀质量损失均随溶蚀时间的增加而增加(84 d后增加缓慢);随矿渣粉掺量的增加而不断减少,即矿渣粉可明显改善硅酸盐水泥的抗溶蚀性能,究其根本在于矿渣粉降低了水泥浆体的CH含量和水化程度。溶蚀84 d的质量损失与浆体中CH含量(0值除外)和水化程度(不掺矿渣粉的除外)呈线性关系,分别为y=0.207 5x–0.015 7,y=0.029 6x–0.125 4。溶蚀84 d的质量损失与水泥初始CaO含量呈对数关系:预养护28 d时回归方程为y=6.059ln(x)–22.164,预养护180 d时回归方程为y=7.612 3ln(x)–27.656,据此可初步判断水泥砂浆抗溶蚀性能。
In the accelerated corrosion 142 d, the leaching mass loss behavior of Portland cement and slag blended cement of three different slag contents (50%, 70% and 90%, in mass fraction) mortar with two different pre-cured ages (28 and 180 d) was investigated. The initial CaO content, calcium hydroxide (CH) content and total hydration degree were analyzed. Based on the relation between CH content and initial CaO content in cement as well as mass loss, the correlation between the initial CaO content and mass loss, and the effect of total hydration degree on mass loss were studied. The results show that the mass loss of all the specimens of two different pre-cured age increase with the increase of leaching time (after 84 d increased slowly), decrease with the increase of addition of slag in blended cement. That is slag can improve the corrosion resistance performance, the fundamental cause of above improvement lies in slag reduced the CH content and hydration degree of blended cement paste. The mass loss with leaching time of 84 d and CH content (0 except) in cement paste, as well as the hydration degree (only slag blended cement) has the following linear relationship respectively. The former is y=0.207 5x-0.015 7, the latter is y=0.029 6x-0.125 4. The mass loss with leaching time of 84 d and initial CaO content in cement has a logarithmic relationship. Pre-eured 28 d, the regression equation is y=6.0591n(x)-22.164. Pre-cured 180 d, the regression equation is y=7.612 3In(x)-27.656. Based on the logarithmic relationship, cement mortar corrosion resistance can be preliminary judged.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2016年第5期634-639,共6页
Journal of The Chinese Ceramic Society
基金
国家"973"计划项目(2009CB623104)
国家自然科学基金(51102181)资助项目
关键词
矿渣混合水泥
氧化钙
氢氧化钙
初始含量
水化程度
溶蚀质量损失
slag blended cement
calcium oxide
calcium hydroxide
initial content
hydration degree
leaching mass loss