| 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. |
| 关键词: C S H粉体 晶种 接触角 水泥水化动力学 |
| DOI：103969/jissn1007 9629201502003 |
| 分类号: |
| 基金项目: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） |
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| Effects of the C S H Powder on the Hydration Process and Mechanism of Cement |
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PENG Xiaoqin, LAN Cong, WANG Shuping, SUI Shiyu, ZENG Lu
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College of Materials Science and Engineering, Chongqing University,Chongqing 400045, China
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| Abstract: |
| 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 permeating height; kinetic parameters, such as reaction rate(K), hydration degree(α), 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 indicate 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. |
| Key words: C S H powder seeding contact angle cement hydration kinetics |
