粒化高炉矿渣作为混凝土细骨料的试验研究

This project is based on the research work that was finished by proposer from 2009 to 2011 in Japan, and it will be studied that the granulated blast furnace slag replace the natural sand as fine aggregate in concrete. The physical property of granulated blast furnace slag is similar to the natural sand, the chemical composition is similar to the ordinary Portland cement. Granulated blast furnace slag has potential hydraulic property, the long term strength of concrete using granulated blast furnace slag as fine aggregate is high, and the durability is well too. Through studying of strength, chemical composition, potential hydraulic property, pore structure and other characteristics of granulated blast furnace slag, and based on analysis of relevant experimental investigation of strength of concrete, the quality evaluation standard of granulated blast furnace slag as fine aggregate for concrete will be established. Through trial mixing experiment of concrete, the method about mixing concrete using granulated blast furnace slag as fine aggregate will be proposed. Focus on the experimental research about mechanical properties of concrete using granulated blast furnace slag as fine aggregate, as a result of this research, the mechanism about potential hydraulic property of granulated blast furnace slag and the mechanism about influence on concrete strength by potential hydraulic property will be revealed, in addition, basic experiment data and application suggestion would be provided in order to use granulated blast furnace slag as fine aggregate in concrete for civil engineering. This project will be filled gaps in the domestic, in order to expand ways about utilization of blast furnace slag, speed up the process of "Zero Discharge" of steel slag and alleviate the contradiction between supply and demand of natural sand for civil engineering, any new ideas and references would be provided for creating the resources saving society.

本项目以申请人2009至2011年在日本的研究工作为基础，拟对粒化高炉矿渣代替天然砂作为混凝土细骨料展开系统的试验研究。粒化高炉矿渣物理性质类似于天然砂、化学成分类似于硅酸盐水泥、具有一定的潜在水硬性，使用粒化高炉矿渣细骨料的混凝土具有长期强度高、耐久性能好的优点。通过对粒化高炉矿渣强度、化学成分、潜在水硬性、细孔结构等特性测试分析、并结合相关混凝土实验研究，初步建立粒化高炉矿渣细骨料品质评定标准。通过混凝土配合试验，给出适合粒化高炉矿渣细骨料混凝土配合方法的建议。重点对使用高炉矿渣细骨料混凝土强度特性进行实验研究，揭示粒化高炉矿渣潜在水硬性的作用机理及对混凝土强度发展的影响机制，为开展在混凝土中粒化利用高炉矿渣细骨料提供基础研究数据和工程应用建议。该研究填补了国内空白，为拓展高炉矿渣的利用途径、加快钢铁废渣"零排放"进程，缓解建设用砂供需矛盾，创建资源节约型现代化社会提供新的思路及参考。

粒化高炉矿渣是钢铁工业的副产物，化学成分类似于普通硅酸盐水泥熟料，主要以玻璃态颗粒为主，具有潜在水硬性，物理性质类似于天然砂。本项目对粒化高炉矿渣作为混凝土细骨料进行了系统的试验研究。结果表明：①相比于天然砂，粒化高炉矿渣的颗粒形状不好且表面孔隙较多、吸水率变化较大、压碎指标远大于天然砂，具有一定的潜在水硬性。②在优化配合比设计条件下，粒化高炉矿渣细骨料混凝土的工作性能优良、可满足工程应用的要求。③粒化高炉矿渣细骨料混凝土的力学性能与普通混凝土接近，由于潜在水硬性的存在，粒化高炉矿渣细骨料混凝土的后期强度增长较大、其长龄期强度有超越同配合条件的天然砂混凝土的趋势。④粒化高炉矿渣细骨料混凝土的干燥收缩性能优于普通混凝土、冻融性能及抗氯离子渗透性能接近普通混凝土，考虑潜在粒化高炉矿渣水硬性的影响、粒化高炉矿渣混凝土的耐久性能优于普通混凝土。研究结论：粒化高炉矿渣可以代替天然砂用作混凝土细骨料。