生态型纯粉煤灰水泥的微观工作机理及宏观性能分析

发布时间：2018-03-26 16:23

本文选题：生态型　切入点：纯粉煤灰水泥　出处：《沈阳建筑大学学报(自然科学版)》2017年02期

【摘要】：目的研发一种常温下可制备、且无需碱活化的生态型纯粉煤灰水泥(EPFC),验证其具有与325R普通硅酸盐水泥相当甚至某些指标超出325R的使用性能.方法采用扫描电镜(SEM)、能量色散谱分析(EDS)、X射线衍射分析(XRD)等手段对原材料和不同龄期的生态型纯粉煤灰水泥开展微观分析,初步确定其水化机制、水化过程等微观工作机理;对EPFC试件进行抗压强度试验,氯离子渗透性能试验,干密度、塌落度、硬度和弹性模量试验,分析其宏观性能.结果粉煤灰中CaO含量较低,会降低溶液中Ca~(2+)和OH~-的浓度,降低pH值,造成粉煤灰中的硅酸盐溶解通常较慢,因此EPFC在超出28 d养生龄期后的一年内还有强度增长.EPFC水化过程非常复杂,水化产物包括氢氧化铝,C-S-H,M-A-S-H和C-A-S-H.EPFC的高早强是因为粉煤灰主要由无定形的富Al富Ca相和石英的结晶相、赤铁矿、游离石灰、方镁石和氧化铝组成.结论 EPFC具有高早强和低密度的特点,可作为快速修补材料以及轻型混凝土原材料混凝土原材料.
[Abstract]:Objective to develop a preparation method at room temperature. The EPFC _ (C) of ecotypic pure fly ash cement without alkali activation is proved to have the same performance as 325R Portland cement or even some indexes beyond 325R. Methods scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to analyze the X-ray diffraction of fly ash cement. Microanalysis of raw materials and ecotypic pure fly ash cement of different ages by means of XRD, The hydration mechanism, hydration process and other microcosmic working mechanisms were preliminarily determined. The compressive strength tests, chloride ion permeability tests, dry density, collapse degree, hardness and elastic modulus tests were carried out on EPFC specimens. Results the content of CaO in fly ash is lower, the concentration of Ca~(2 and OH- in the solution will be decreased, and the pH value will be decreased, resulting in the dissolution of silicate in fly ash is usually slower. Therefore, the hydration process of EPFC within one year after 28 days of health age is very complicated. The hydration products include aluminum hydroxide C-S-HGM-A-S-H and high early strength of C-A-S-H.EPFC because the fly ash is mainly composed of amorphous Al-rich Ca phase and quartz crystalline phase. Hematite, free lime, periclase and alumina. Conclusion EPFC has the characteristics of high early strength and low density, and can be used as a fast repair material and a raw material for light concrete raw material concrete.
【作者单位】：山西大学土木工程系;河北工业大学土木与交通学院;
【基金】：国家自然科学基金项目(41371359) 山西省科技计划项目(2015021132) 山西省大学生创新创业训练计划项目(201610108017)
【分类号】：TQ172.1

【相似文献】