硅酸盐学报

碱金属硫酸盐与减水剂对水泥浆体抗泌水能力的影响

作者：韩松1 阎培渝2 安明喆1

单位：1. 北京交通大学建筑工程系北京 100044 2. 清华大学土木工程系土木工程安全与耐久教育部重点实验室北京 100084

分类号：TU528.042.2

出版年,卷(期):页码：2016,44(11):0-0

DOI：10.14062/j.issn.0454-5648.2016.11.11

摘要：

通过测量水泥浆体的zeta电位，研究了碱金属硫酸盐对掺有萘系或聚羧酸减水剂的水泥浆体内自由溶液量的影响规律，以及碱金属硫酸盐和减水剂掺量对水泥浆体的保水能力和水泥颗粒之间作用力的影响，并讨论了浆体抗泌水能力变化的机理。结果表明：萘系减水剂和聚羧酸减水剂的加入都会降低浆体的自由溶液量，增加浆体保水能力；但在超过饱和掺量后，萘系减水剂会引起浆体内部吸附水量降低，对浆体产生不利影响，聚羧酸减水剂则没有类似作用。当水泥浆体中掺入碱金属硫酸盐时，聚羧酸减水剂受到的影响要显著小于萘系减水剂。在掺有减水剂的水泥浆体中，掺入适量的碱金属硫酸盐可以提高浆体的保水能力，降低泌水风险。萘系减水剂对应的碱金属硫酸盐最佳掺量约为2.7% SO3当量，聚羧酸减水剂则为2.5% SO3当量。碱金属硫酸盐通过快速溶出硫酸根离子，影响水泥颗粒表面动电特性，进而影响浆体的抗泌水能力；溶解速率较慢的二水石膏没有类似作用。

The zeta potential of the cement pastes was determined to investigate the influence of alkali sulfate on the free solution amount of cement paste with naphthalene (NS) or polycarboxylate (PCE) as superplasticizers. The water-holding capacity of cement paste and force between the cement particles were analyzed. The corresponding mechanism with respect to alkali sulfate and superplasticizer effects on the bleeding resistance of cement paste was discussed. The results show that free solution amount decreases and water-holding capacity improves after adding NS and PCE. However, the overdose NS reduces the amount of adsorbed solution in paste, which adversely affects the cement paste on the water-holding capacity, but PCE does not have such an effect. The effect of alkali sulfate on PCE is less than that on NS. In cement paste with superplasticizer, the appropriate amount of alkali sulfate improves the water-holding capacity of cement paste and reduces the risk of bleeding. The optimal content of sulfate is approximately 2.7% SO3 for NS and 2.5% SO3 for PCE. Alkali sulfate affects the zeta potential of cement particle surface via the rapid dissolution of sulfate ion, thereby increasing the bleeding resistance of cement paste. Gypsum has no effect, thus causing the slower dissolution.

基金项目：

中央高校基本科研业务费专项资金(2016JBM045)；国家自然科学基金(51408037，51578049)资助项目。

作者简介：

韩松(1984—)，男，讲师。

参考文献：

[1] 李崇智, 张方财, 廖伟, 等. 水泥浆沉淀泌水模型以及混凝土离析泌水问题的探讨[J]. 混凝土, 2015(9): 69–71.
Li Chongzhi, Zhang Fangcai, Liao Wei, et al. Concrete (in Chinese), 2015(9): 69–71.
[2] 韩松, 阎培渝, 安明喆. 减水剂与低硫酸盐含量水泥的相容性研究[J]. 硅酸盐学报, 2014, 42(8): 981–988.
HAN Song, YAN Peiyu, AN Minzhe. J Chin Ceram Soc, 2014, 42(8): 981–988.
[3] AGARWAL S K, IRSHAD M, MALHOTRA S K. Compatibility of superplasticizers with different cements[J]. Constr Build Mater, 2000, 14: 253–259.
[4] 覃维祖. 初龄期混凝土的泌水、沉降、塑性收缩与开裂[J]. 商品混凝土, 2006(1): 1–9.
QIN Weizhu. Ready-Mix Concrete (in Chinese), 2006(1): 1–9.
[5] 刘加平, 刘建忠, 田倩, 等. 外加剂改进混凝土泌水的试验研究[J]. 混凝土与水泥制品, 2004(4): 14–6.
LIU Jiaping, LIU Jianzhong, TIAN Qian, et al. China Concr Cem Prod (in Chinese), 2004(4): 14–16.
[6] HAN Song, YAN Peiyu, KONG Xiangming. Study on the compatibility of cement-superplasticizer system based on the amount of free solution[J]. Sci China Technol, 2011, 54(1): 183–189.
[7] ELKE K, OZLEM C, KOENRAAD V B, et al. Effect of free water removal from early-age hydrated cement pasteson thermal analysis[J]. Constr Build Mater, 2009, 23: 3431–3438.
[8] MOHR B J, HOOD K L. Influence of bleed water reabsorption on cement paste autogenous deformation [J]. Cem Concr Res, 2010, 40: 220–225.
[9] LI J Z, ZHANG Y, CUI X M. The influence of free water content on dielectric properties of alkali active slag cement paste[J]. J Wuhan Univ Techno: Mater Sci Ed, 2007, 12: 774–777.
[10] WU Q, AN X, LIU C. Effect of polycarboxylate-type superplasticizer on the paste fluidity based on the water film thickness of flocs[J]. Sci China Technol Sci, 2014, 57(8): 1522–1531.
[11] 阎培渝, 王悦. 可溶碱对水泥/氨基磺酸盐减水剂相容性的影响[J]. 建筑材料学报, 2006, 9(5): 576–580.
YAN Peiyu, WANG Yue. J Build Mater (in Chinese), 2006, 9(5): 576–580.
[12] 孙振平, 蒋正武, 王玉吉, 等. 水泥含碱量对萘系高效减水剂作用效果的影响[J]. 混凝土, 2002(4): 6–18
Sun Zhenping, Jiang Zhengwu, Wang Yyujie, et al. Concrete (in Chinese), 2002(4): 6–18.
[13] KIM Byung-Gi, JIANG Shiping, JOLICOEUR Carmel, et al. The adsorption behaveior of PNS superplasticizer and its relation to fluidity of cement paste[J]. Cem Concr Res, 2000, 30: 887–893.
[14] 韩松, 阎培渝. 硫酸盐对萘系减水剂与水泥相容性的影响[J]. 硅酸盐学报, 2010 (9): 1765–1770.
Han Song, Yan Peiyu. J Chin Ceram Soc, 2010 (9): 1765–1770.
[15] HAN Song, YAN Peiyu, LIU Rengguang. Study on the hydration product of cement in early age using TEM [J]. Sci China Technol Sci, 2012, 55(8): 2284–2290.
[16] HOU S S, KONG X M, CAO E X, et al. Effects of chemical structure on the properties of polycarboxylate-type superplasticizer in cementitious systems[J]. J Chin Ceram Soc, 2010, 38(9): 1698–1701.
[17] HAN Song, PLANK J. Mechanistic study on the effect of sulfate ions on polycarboxylate superplasticisers in cement[J]. Adv Cem Res, 2013, 25(4): 200–207.
[18] JIANG S P, KIM B G, AITEIN P C. Importance of adequate soluble alkali content to ensure cement/superplasticizer compatibility[J]. Cem Concr Res, 1999, 29: 71–78.
[19] MAGAROTTO R, TORRESAN I, ZEMINIAN N. Effect of alkaline sulfates on performance of superplasticizers[C]//Proceeding of the 11th International Congress on the Chemistry of Cement: Cement’s Contribution to development in the 21st Century，Durban (South Africa)，2003: 569–580.
[20] 韩松. 石膏与碱金属硫酸盐对减水剂与水泥相容性的影响机理[D]. 北京: 清华大学, 2012.
Han Song. The influencing mechanism of gypsum and alkali sulfate on the compatibility of cement with superplasticizers[in Chinese, dissertation]. Tsinghua University (in Chinese, dissertation). Beijing: Tsinghua University. 2012.

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