水化硅酸钙粉体对水泥水化反应过程及机理的影响  

Effects of the C-S-H Powder on the Hydration Process and Mechanism of Cement

作　　者：彭小芹 兰聪[1] 王淑萍[1] 眭世玉 曾路[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400045 [2]东南大学材料科学与工程学院,江苏南京210096

出　　处：《建筑材料学报》2015年第2期195-201,共7页Journal of Building Materials

基　　金：国家自然科学基金资助项目(50972171);科技部国际合作项目(2009DFR50450);重庆大学大型仪器开放基金资助项目(2013121513)

摘　　要：将水化硅酸钙（C-S-H）粉体掺入水泥浆中,研究其对水泥水化动力学和反应机理的影响.利用TAM air微量热仪,测量了掺入C-S-H粉体后水泥的水化速率和水化热;采用透过高度法测试了C-S-H粉体的接触角;运用水化动力学分析方法,确定了掺C-S-H粉体后水泥水化反应速率常数K,水化度α,反应级数n等动力学参数;并根据动力学微分曲线评价了C-S-H粉体对水泥水化机理和水化过程的影响.结果表明：C-S-H粉体能降低水泥的水化热总量和成核势垒,并使其水化放热峰提前;C-S-H粉体在水泥水化反应过程中主要起晶种作用;在一定C-S-H粉体掺量（质量分数）范围（1％～3％）内,水泥水化过程符合结晶成核与晶体生长（NG过程）-相边界反应（Ⅰ过程）-扩散（D过程）的水化机理,C-S-H粉体促进了NG过程,对Ⅰ过程有一定的削弱作用,而对D过程影响很小.Addition of the calcium silicate hydrate（C-S-H） powder to cement paste was aimed to investigate its influence on the cement hydration kinetics and mechanism. Hydration rate and hydration heat were measured by TAM air calorimetry. The contact-angle of the C-S-H powder was evaluated by the permea- ting height; kinetic parameters, such as reaction rate（K）, hydration degree（a）, and reaction order（n） were evaluated according to the analysis of the hydration kinetics. Additionally, the influence of the C-S-H powder on hydration mechanism of cement was discussed according to the differential curve. Results indi- cate that the time to reach the rate peak and the total heat of cement hydration decrease with the addition of C-S-H powder, and nucleation barrier is reduced as well, which is attributed to the seeding effect of the C-S-H additives by providing new nucleation sites. Given a certain amount of C-S-H（1% to 3% by mass）, hydration mechanism is described as nucleation and crystal growth（NG） -interaction at phase boundaries （I）-diffusion（D）. Addition of C-S-H powder can accelerate the NG process, and has inhibition effect on the I process. It has no influence on the D process.

关 键 词：C-S-H粉体 晶种 接触角 水泥水化动力学 

分 类 号：TQ172.11[化学工程—水泥工业]