滞水添加对不同液体速凝剂作用的影响  

Influences of Lagging Addition Behind Water on the Effect of Different Liquid Accelerators

作　　者：何廷树[1] 刘莎 袁倩男 杨仁和 官梦芹 徐一伦 HE Tingshu;LIU Sha;YUAN Qiannan;YANG Renhe;GUAN Mengqin;XU Yilun(School of Materials Science and Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Xiamen Construction Science Study Institute,Xiamen 361004,China;Shaanxi You Bang New Material Technology Co.,Ltd.,Xi’an 712046,China)

机构地区：[1]西安建筑科技大学材料科学与工程学院,陕西西安710055 [2]厦门市建筑科学研究院,福建厦门361004 [3]陕西友邦新材料科技有限公司,陕西西安712046

出　　处：《材料科学与工程学报》2022年第5期816-822,共7页Journal of Materials Science and Engineering

基　　金：垒知创新基金资助项目(JYGrp20190501)。

摘　　要：采用基准水泥和普通硅酸盐水泥,对比研究了滞水添加时间对偏铝酸钠基有碱(AL)、硫酸铝基无碱(AF)两种液体速凝剂的凝结时间和抗压强度的影响,结果表明:两种速凝剂的滞水添加均会明显延长水泥净浆的初、终凝时间,且滞水时间对AF的影响更为显著;但滞水添加时间对掺两种速凝剂的胶砂1 d和28 d抗压强度均影响不大;滞水30 min后添加速凝剂相较于直接添加会明显降低水泥净浆早期水化温峰,且掺AF净浆的温峰降低幅度更大;主要原因是水泥初期生成的AFt覆盖于矿物表面阻碍了滞水添加的速凝剂与水泥的作用;滞水添加AL生成的AFt易转化为AFm,故滞水添加方式对降低AL的促凝作用小于对降低AF的作用。By using reference cement and ordinary Portland cement, the influences of lagging addition time behind water of two kinds of liquid accelerators, i.e. sodium meta aluminate-based alkali(AL) and aluminum sulfate-based alkali-free(AF), on their setting time and compressive strength were contrastively investigated. The results showed that the lagging addition behind water obviously prolonged the initial and final setting time of cement pastes with two kinds of liquid accelerators, and had a more significant effect on cement paste with AF. However, the lagging addition behind water had little effect on 1 d and 28 d compressive strength of mortars with two kinds of liquid accelerators. The lagging 30 min addition behind water of liquid accelerators significantly reduced the early hydration temperature peak of cement paste compared with the direct addition, and the decreasing amplitude of temperature peak of cement paste with AF was more. AFt generated in the early stage of cement hydration covered the mineral surface, which hindered the actions between the added accelerator lagging behind water and cement. This was the main reason why the lagging addition of liquid accelerators would prolong the setting time of cement paste. AFt produced by adding AL in stagnant water would be easy to change into AFm, so the lagging addition behind water reduced the setting promotion effect of AL less than did that of AF.

关 键 词：液体速凝剂 滞水添加 凝结时间 抗压强度 钙矾石 

分 类 号：TU528.042.7[建筑科学—建筑技术科学]