| 摘要: |
| 利用硅酸盐水泥-硫铝酸盐水泥-脱硫石膏三元胶凝体系制备修补砂浆，研究了酒石酸、硼砂及六偏磷酸钠等缓凝剂及其复掺时对修补砂浆性能的影响.结果表明：酒石酸在修补砂浆中无明显的缓凝作用，并且显著降低了修补砂浆的流动度、力学性能和干燥收缩率；硼砂和六偏磷酸钠均能有效延长修补砂浆的凝结时间，改善其流动度；硼砂虽能提高修补砂浆的强度，但增大了干燥收缩率；六偏磷酸钠有利于修补砂浆的中后期强度，显著降低了干燥收缩率；3种缓凝剂均使得修补砂浆的拉伸黏结强度有所降低，复掺缓凝剂的影响介于单掺2种相应缓凝剂的作用效果之间. |
| 关键词: 修补砂浆 缓凝剂 三元胶凝体系 凝结时间 强度 干燥收缩率 |
| DOI：10.3969/j.issn.1007-9629.2023.06.013 |
| 分类号:TU525.9 |
| 基金项目:“十三五”国家重点研发计划项目（2018YFD1101003）；上海市住房与城乡建设委员会科研项目 （2020-001-009， 2023-005-001）；固废资源化利用与节能建材国家重点实验室开放基金 |
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| Effects of Retarders on the Properties of Repair Mortar with PC-CSA-FDG Ternary Binder |
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ZHANG Guofang1,2,3, WANG Jiangfu1,2, WANG Xianghong1,2, WANG Peiming1,2
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1.Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education， Tongji University， Shanghai 201804， China;2.School of Materials Science and Engineering， Tongji University， Shanghai 201804， China;3.Research Center of Intelligent Evaluation and Restoration Engineering Technology of Urban Pipe Network of Shanghai Water Bureau， Shanghai 201900， China
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| Abstract: |
| Portland cement-calcium sulphoaluminate cement-flue gas desulfurization gypsum ternary binder （PC-CSC- FDG ternary binder）was used to prepare repair mortars， and the effects of tartaric acid， borax， sodium hexametaphosphate and their mixtures on the properties of the repair mortar were investigated. The results show that tartaric acid has no retardation effect， and can significantly reduce the fluidity， mechanical properties and drying shrinkage of the repair mortar. Borax and sodium hexametaphosphate can significantly prolong the setting time and improve the fluidity of repair mortar. Borax has negligible influence on the flexural strength， but can significantly increase the compressive strength and the drying shrinkage. Sodium hexametaphosphate can slightly reduce the early strength， but improve the strength at the middle and late ages， and significantly reduce the drying shrinkage. All these three retarders yield decrease of tensile bond strength to some extent. The effects of retarder double-mixture on properties are the effect superpositions of the corresponding retarders. |
| Key words: repair mortar retarder ternary binder setting time strength drying shrinkage |
