表层混凝土纳米SiO2改性研究

项目名称： 表层混凝土纳米SiO2改性研究

项目编号： No.51302105

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 侯鹏坤

作者单位： 济南大学

项目金额： 25万元

中文摘要： 混凝土表层通常最容易受到环境介质的侵蚀，提高其致密度、优化其中水泥石组成可有效提高混凝土抗侵蚀性。申请项目根据纳米SiO2可显著提高水泥石密实度并降低Ca(OH)2含量和凝胶Ca/Si比的前期研究结果，将纳米SiO2对水泥石改性用于提高混凝土表层的密实性，通过研究表层混凝土所处环境温湿度以及孔溶液碱度作用下的纳米SiO2对水泥和其他辅助胶凝材料水化产物以及自身火山灰反应的影响规律，确定有利于提高混凝土表层密实度的凝胶Ca/Si比、水泥石组成、形貌和孔结构；采用荧光示踪法研究纳米SiO2在混凝土中的渗透性以及影响因素，探索提高纳米SiO2在混凝土表层中的反应程度和速度的措施；通过宏观试验测定纳米SiO2改性后混凝土表层抗侵蚀性能的变化规律，确定纳米SiO2在混凝土表层改性中的作用。项目研究结果将为混凝土表层改性提供新的思路，相关研究结果还将为有关纳米SiO2在水泥混凝土中应用研究提供参考。

中文关键词： 混凝土；表面处理；纳米二氧化硅；耐久性；

英文摘要： Surface concrete is the most vulnerable part of concrete structure to environment. By densifying its structure and optimizing the chemical components, the anti-corrosion property of surface concrete can be highly improved. It has been suggested that nanosilica can greatly improve the packing density of hydration products, lower Ca(OH)2 content and Ca/Si ratio of C-S-H gel. In this project, the improvement of surface concrete quality is going to be studied with the modification effect of nanosilica. Optimal Ca/Si ratio, chemical compositions, morphology and porosity of hydration products are determined through investigations of the properties of hydrates of cement and suplimentary cementitious materials and its own pozzolanic reactivity of nanosilica under the hydration temperature,humidity and alkalinity of pore solution of surface concrete. The transport characteristics of nanosilica in concrete is studied through fluorescent tracing technique and measures of improving the hydration degree and hydration rate of nanosilica will be proposed. Based on the study of the anti-corrosion property of surface concrete after modification, the influences of nanosilica on the properties of concrete will be determined.It is expected that these studies may provide new idea for the study of the modification of surface concret

英文关键词： concrete；surface treatment；nanosilica；durability；