低温环境下含石灰石粉水泥基材料抗硫酸盐侵蚀性能研究  

Sulfate Resistance Performance of Cement-Based Materials ContainingLimestone Powder at Low Temperature

作　　者：李雪峰[1,2] LI Xuefeng(Research Institute of Highway Ministry of Transport,Beijing 100088,China;National Engineering Laboratory for Bridge Structure Safety Technology,Beijing 100088,China)

机构地区：[1]交通运输部公路科学研究院,北京100088 [2]桥梁结构安全技术国家工程实验室,北京100088

出　　处：《硅酸盐通报》2024年第7期2372-2382,共11页Bulletin of the Chinese Ceramic Society

基　　金：新疆维吾尔自治区重大科技专项(2020A03003-4);中交集团特大科技研发项目(2017-ZJKJ-01);中央级公益性科研院所基本科研业务费项目(2021-9047b)。

摘　　要：为提升低温硫酸盐环境下含石灰石粉水泥基材料的抗硫酸盐侵蚀性能,采用脉冲电场加速硫酸盐侵蚀,通过观测试件外观形貌变化及利用XRD和FT-IR测定腐蚀物微观组分,对掺不同矿物掺合料的含石灰石粉水泥基材料抗硫酸盐侵蚀性能及机理开展研究。结果表明:掺加矿物掺合料可在不同程度上改善含石灰石粉水泥基材料的低温抗硫酸盐侵蚀性能,且复掺较单掺时的整体侵蚀抑制效果更加显著,但需满足矿物掺合料的最低掺量要求;建议单掺时水泥基材料中粉煤灰或矿粉的质量占比应分别不低于30%和50%,复掺时粉煤灰与矿粉的质量占比为50%~70%,且二者质量比以1.0∶1.5~1.0∶2.5为宜。此外,含石灰石粉水泥基材料在发生碳硫硅钙石型硫酸盐侵蚀(TSA)过程中,碳硫硅钙石衍射峰主要由钙矾石衍射峰右移后形成,表明其生成以钙矾石转化为主。因此,有效抑制钙矾石的生成是抑制含石灰石粉水泥基材料发生TSA的重点。In order to improve sulfate resistance performance of cement-based materials containing limestone powder at low temperature,the sulfate resistance and mechanism of cement-based materials containing limestone powder mixed with different mineral admixtures were studied by using pulsed electrical field to accelerate sulfate erosion,observing the changes of specimen appearance and measuring the microscopic components of the corrosion material by XRD and FT-IR.The results indicate that the incorporation of mineral admixtures can enhance the sulfate resistance performance of cement-based materials containing limestone powder in low-temperature to some extent,and the inhibitory effect of combined mineral admixture is found to be more pronounced compared with single mineral admixture.However,the minimum content requirements of mineral admixtures should be met.It is suggested that,in the case of single mineral admixture,the mass proportion of fly ash or slag powder in cement-based materials should not be less than 30%and 50%,respectively.The sum of fly ash and slag powder content should be 50%~70%in the case of combined mineral admixture,and the mass ratio of fly ash and slag powder is 1.0∶1.5~1.0∶2.5.In addition,during thaumasite form of sulfate attack(TSA)of cement-based materials containing limestene powder,the diffraction peak of thaumasite is mainly formed by the rightward shift of ettringite diffraction peak,indicating that the formation of thaumasite is mainly formed by the transformation of ettringite.Therefore,the effective inhibition of formation of ettringite is the key point to inhibit TSA for cement-based materials containing limestone powder.

关 键 词：水泥基材料 石灰石粉 碳硫硅钙石 低温 抗硫酸盐侵蚀 脉冲电场 

分 类 号：TU525[建筑科学—建筑技术科学]