硼砂/三乙醇胺复合缓凝剂对磷酸钾镁水泥水化硬化性能的影响

摘要/Abstract

摘要： 磷酸钾镁水泥(MKPC)的速凝特性限制了其在更多工程领域的应用发展,有效延长凝结时间是其工程化应用的关键技术之一。本研究使用硼砂/三乙醇胺复合缓凝剂,深入研究了其对磷酸钾镁水泥凝结时间、抗压强度、物相组成、微观形貌、孔结构和水化放热等特性的影响,并探讨了缓凝机理。结果表明:在保障7 d抗压强度大于20 MPa条件下,复合缓凝剂的使用,可实现26~100 min的凝结时间调控;三乙醇胺分子包覆MgO颗粒,发挥阻水作用,从而显著降低水化反应的标准水化放热速率与标准水化放热量,达到缓凝效果;试样中K-鸟粪石含量的减少与大于10 nm孔隙体积的增加是削弱抗压强度的主要原因。

关键词: 磷酸钾镁水泥, 三乙醇胺, K-鸟粪石, 缓凝, 孔隙率, 水化热

Abstract: The rapid setting characteristic of potassium magnesium phosphate cement (MKPC) limits its application and development in engineering fields. Effectively prolonging the setting time is one of the key technologies for its engineering application. In this study, the effect of borax/triethanolamine composited retarder on the setting time, compressive strength, phase composition, micromorphology, pore structure and hydration heat release properties of MKPC was studied, and the retarding mechanism was discussed. The results show that the setting time of 26~100 min can be controlled by using the composited retarder under the condition that the 7 d compressive strength is greater than 20 MPa. Triethanolamine molecule is adsorbed on the surface of MgO and plays a role in water blocking, which significantly reduces the standard hydration heat release rate and standard hydration heat release, and achieves the retarding effect. The decrease of K-struvite content and the increase of pore (larger than 10 nm) volume are the main reasons for the weakening of compressive strength.

Key words: potassium magnesium phosphate cement, triethanolamine, K-struvite, delayed coagulation, porosity, hydration heat

中图分类号:

TB321

叶飞, 师文杰, 吴博, 谭高明, 马雪. 硼砂/三乙醇胺复合缓凝剂对磷酸钾镁水泥水化硬化性能的影响[J]. 硅酸盐通报, 2023, 42(2): 403-410.

YE Fei, SHI Wenjie, WU Bo, TAN Gaoming, MA Xue. Effect of Borax/Triethanolamine Composited Retarder on Hydration and Hardening of Potassium Magnesium Phosphate Cement[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2023, 42(2): 403-410.

参考文献

[1] 温金保, 唐修生, 黄国泓, 等. 磷酸镁水泥快速修补材料的性能试验[J]. 水利水电科技进展, 2017, 37(2): 82-87.
WEN J B, TANG X S, HUANG G H, et al. Performance testing on rapid repair materials of magnesium phosphate cement[J]. Advances in Science and Technology of Water Resources, 2017, 37(2): 82-87 (in Chinese).
[2] 赖振宇, 钱觉时, 卢忠远, 等. 原料及配比对磷酸镁水泥性能影响的研究[J]. 武汉理工大学学报, 2011, 33(10): 16-20.
LAI Z Y, QIAN J S, LU Z Y, et al. Effects of raw materials and compositions to the properties of magnesium phosphate cement[J]. Journal of Wuhan University of Technology, 2011, 33(10): 16-20 (in Chinese).
[3] ZHANG Q S, CAO X, MA R, et al. Solid waste-based magnesium phosphate cements: preparation, performance and solidification/stabilization mechanism[J]. Construction and Building Materials, 2021, 297: 123761.
[4] 王建苗, 高越青, 詹培敏, 等. 磷酸钾镁水泥修补材料研究综述[J]. 硅酸盐通报, 2021, 40(11): 3533-3543.
WANG J M, GAO Y Q, ZHAN P M, et al. Research review of magnesium potassium phosphate cement repair materials[J]. Bulletin of the Chinese Ceramic Society, 2021, 40(11): 3533-3543 (in Chinese).
[5] ZHU D, LI Z. High-early-strength magnesium phosphate cement with fly ash[J]. ACI Materials Journal, 2005, 102(6): 375-381.
[6] JIANG H L, ZHANG J W, LI T, et al. Feasibility analysis of magnesium phosphate cement as a repair material for base slab of China railway track system II ballastless track[J]. Construction and Building Materials, 2022, 326: 126821.
[7] HAQUE M A, CHEN B, LIU Y T. The role of bauxite and fly-ash on the water stability and microstructural densification of magnesium phosphate cement composites[J]. Construction and Building Materials, 2020, 260: 119953.
[8] 戴俊. 磷酸钾镁水泥缓凝剂及修补砂浆配合比设计方法研究[D]. 南京: 东南大学, 2019.
DAI J. Research on rertarder of potassium magnesium phosphate cement and mix design method for repair mortar[D]. Nanjing: Southeast University, 2019 (in Chinese).
[9] LAHALLE H, CAU DIT COUMES C, MERCIER C, et al. Influence of the w/c ratio on the hydration process of a magnesium phosphate cement and on its retardation by boric acid[J]. Cement and Concrete Research, 2018, 109: 159-174.
[10] 常远, 史才军, 杨楠, 等. 不同细度MgO对磷酸钾镁水泥性能的影响[J]. 硅酸盐学报, 2013, 41(4): 492-499.
CHANG Y, SHI C J, YANG N, et al. Effect of fineness of magnesium oxide on properties of magnesium potassium phosphate cement[J]. Journal of the Chinese Ceramic Society, 2013, 41(4): 492-499 (in Chinese).
[11] 齐召庆, 徐哲, 孙运亮, 等. 原材料及配比对磷酸镁水泥强度的影响[J]. 当代化工, 2015, 44(11): 2581-2584.
QI Z Q, XU Z, SUN Y L, et al. Effect of raw materials and their ratio on compressive strength of magnesium phosphate cement[J]. Contemporary Chemical Industry, 2015, 44(11): 2581-2584 (in Chinese).
[12] 韦宇, 周新涛, 黄静, 等. 缓凝剂对磷酸镁水泥性能及其水化机制影响研究进展[J]. 材料导报, 2022, 36(4): 77-83.
WEI Y, ZHOU X T, HUANG J, et al. Research progress on the effects of retarders on the properties and hydration mechanism of magnesium phosphate cement[J]. Materials Reports, 2022, 36(4): 77-83 (in Chinese).
[13] 段新勇, 吕淑珍, 赖振宇, 等. 多元复合缓凝剂制备及其对磷酸镁水泥性能的影响[J]. 武汉理工大学学报, 2014, 36(10): 20-25.
DUAN X Y, LV S Z, LAI Z Y, et al. Preparation of a multi-composite retarder and its effect on properties of magnesium phosphate cement[J]. Journal of Wuhan University of Technology, 2014, 36(10): 20-25 (in Chinese).
[14] RIBEIRO D V, PAULA G R, MORELLI M R. Use of microwave oven in the calcination of MgO and effect on the properties of magnesium phosphate cement[J]. Construction and Building Materials, 2019, 198: 619-628.
[15] HALL D A, STEVENS R, EL-JAZAIRI B. The effect of retarders on the microstructure and mechanical properties of magnesia-phosphate cement mortar[J]. Cement and Concrete Research, 2001, 31(3): 455-465.
[16] 高瑞. 改性磷酸镁水泥基材料的性能研究[D]. 西安: 西安建筑科技大学, 2014.
GAO R. Performance studies on magnesium phosphate cement[D]. Xi'an: Xi'an University of Architecture and Technology, 2014 (in Chinese).
[17] YANG Q B, WU X L. Factors influencing properties of phosphate cement-based binder for rapid repair of concrete[J]. Cement and Concrete Research, 1999, 29(3): 389-396.
[18] 中华人民共和国住房和城乡建设部, 国家市场监督管理总局. 混凝土物理力学性能试验方法标准: GB/T 50081—2019[S]. 北京: 中国建筑工业出版社, 2019.
Ministry of Housing and Urban-Rural Development of the People's Republic of China, State Administration for Market Regulation. Test method standard for physical and mechanical properties of concrete: GB/T 50081—2019[S]. Beijing: China Architecture and Building Press, 2019 (in Chinese).
[19] 中华人民共和国质量监督检验检疫总局. 水泥标准稠度用水量、凝结时间、安定性检验方法: GB/T 1346—2011[S]. 北京: 中国标准出版社, 2011.
General Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China. Test method for water consumption, setting time and stability of cement standard consistency: GB/T 1346—2011[S]. Beijing: Standards Press of China, 2011 (in Chinese).
[20] 王二强, 王冬, 刘兴华. 磷酸镁水泥缓凝剂的研究[J]. 混凝土, 2012(9): 86-88.
WANG E Q, WANG D, LIU X H. Research on retarders of magnesia phosphate cement[J]. Concrete, 2012(9): 86-88 (in Chinese).
[21] 赖振宇. 磷酸镁水泥固化中低放射性废物研究[D]. 重庆: 重庆大学, 2012.
LAI Z Y. Immobilization of medium and low level radioactive wastes by magnesium phosphate cement[D]. Chongqing: Chongqing University, 2012 (in Chinese).
[22] DING Z, DONG B Q, XING F, et al. Cementing mechanism of potassium phosphate based magnesium phosphate cement[J]. Ceramics International, 2012, 38(8): 6281-6288.
[23] LOTHENBACH B, XU B W, WINNEFELD F. Thermodynamic data for magnesium (potassium) phosphates[J]. Applied Geochemistry, 2019, 111: 104450.
[24] 杨元全. 磷酸钾镁水泥水化行为及其热动力学模拟研究[D]. 大连: 大连理工大学, 2020.
YANG Y Q. Hydration behaviors of magnesium potassium phosphate cement system and its thermodynamic simulation[D]. Dalian: Dalian University of Technology, 2020 (in Chinese).
[25] LI Y, LI J Q. Capillary tension theory for prediction of early autogenous shrinkage of self-consolidating concrete[J]. Construction and Building Materials, 2014, 53: 511-516.
[26] LI Y, LIN H, HEJAZI S M A S, et al. The effect of low temperature phase change material of hydrated salt on the performance of magnesium phosphate cement[J]. Construction and Building Materials, 2017, 149: 272-278.
[27] ZHANG J X, FUJIWARA T, Resistance to frost damage of concrete with various mix proportions under salty condition, frost resistance of concrete, RILEM Proceedings PRO. Cachan Cedex, France, RILEM Publications Carl, 2002, 367-374.