肯尼亚天然火山灰质材料对水泥水化性能的影响  

Influence of natural pozzolanic materials in Kenya on hydration process of cement

作　　者：李立 关青锋 刘金国 夏京亮 周永祥 冷发光 LI Li;GUAN Qingfeng;LIU Jinguo;XIA Jingliang;ZHOU Yongxiang;LENG Faguang(Luzhou Vocational and Technical College,Luzhou 646000 China;China Academy of Building Research,Beijing 100013,China;National Engineering Research Center Building Technology,Beijing 100013,China;Building Materials of CABR Co.,Ltd.,Beijing 100013,China;Weifang Luyuan Building Materials Co.,Ltd.,Weifang 261208,China)

机构地区：[1]泸州职业技术学院,四川泸州646000 [2]中国建筑科学研究院有限公司,北京100013 [3]国家建筑工程技术研究中心,北京100013 [4]建研建材有限公司,北京100013 [5]潍坊鲁元建材有限公司,山东潍坊261208

出　　处：《混凝土》2020年第11期83-88,共6页Concrete

摘　　要：开采肯尼亚当地天然火山灰质材料以建设蒙巴萨-内罗毕铁路具有重要意义,为研究该天然火山灰质材料对水泥水化性能的影响,以粉煤灰和石英粉为参照物,采用当地凝灰岩、火山渣分别替代30%水泥研究净浆凝结时间、活性指数和水化放热量,发现凝灰岩和火山渣均具有一定的促凝效应,凝灰岩促凝效应更明显;进一步粉磨火山渣至不同细度,发现随着火山渣比表面积的增大,其促凝效应呈现增大趋势;火山渣活性指数比凝灰岩高,但低于粉煤灰;进一步粉磨火山渣到不同细度,发现增大火山渣比表面积可提高其活性指数;掺入两种天然火山灰质材料和粉煤灰均能够降低水化放热量。XRD和热重测试结果显示磨细凝灰岩和磨细火山渣均存在火山灰活性,后者的活性更高。It is important to explore the natural pozzolanic materials located in Kenya to construct the Mombasa-Nairobi railway project.To investigate the influence of the natural pozzolan on the hydration process of cement,this study selected local tuff and volcanic cinder to replace 30%cement to measure the setting time,activity index and hydration heat evolution with the refer materials including fly ash and quartz.The testing results show that both the tuff and volcanic cinder exhibited coagulant effect and the former was more obvious.When volcanic cinder was grounded into a finer level,its coagulant effect was amplified as the specific surface area increased.The activity index of volcanic cinder was higher than that of tuff but less than that of fly ash,and it could be improved by increasing the specific surface area of the particle.Adding this two pozzolanic materials could reduce the hydration heat evolution of cementitious systems,while the results of XRD and DT-TGA demonstrated the pozzolanic activity of fine tuff and volcanic cinder and the value of the later was more significant.

关 键 词：天然火山灰质材料 凝结时间 活性指数 水化热 火山灰活性 

分 类 号：TU528.041[建筑科学—建筑技术科学]