碳化养护对大掺量钢渣砂浆的力学性能及显微结构的影响  

Effect of Accelerated Carbonation Curing on Mechanical Property and Microstructure of High Volume Steel Slag Mortar

作　　者：曾海马 刘志超 王发洲[1,2] ZENG Haima;LIU Zhichao;WANG Fazhou(State Key Laboratory of Silicate Materials for Architectures,Wuhan 430070,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]硅酸盐建筑材料国家重点实验室,武汉430070 [2]武汉理工大学材料科学与工程学院,武汉430070

出　　处：《硅酸盐学报》2020年第11期1801-1807,共7页Journal of The Chinese Ceramic Society

基　　金：国家重点研发项目-政府间国际科技创新合作重点专项(2018YFE0106300);国家自然科学基金(51672200,51702242,51925205);湖北省技术创新专项重大项目(2018AAA004)。

摘　　要：提出一种基于最紧密堆积材料体系设计理论的可浇筑成型的高性能可碳化混凝土(HPCC)。以钢渣粉为主要胶凝组分,利用少量普通硅酸盐水泥的高水化活性提供脱模强度,掺入适量硅灰提高材料体系的密实度,研究了快速碳化养护对HPCC的力学性能与显微结构的影响规律。结果表明:1 d密封养护后HPCC的抗压强度为5.2 MPa,经干燥预处理与24 h碳化养护后HPCC的抗压强度接近90 MPa;适当的干燥预处理有利于碳化反应的进行,且最佳失水率为74.4%;碳化反应形成的碳酸钙晶体以方解石为主,含微量文石,在最紧密堆积体系内填充并进一步密实基体结构是HPCC高强的主要作用机理;碳化养护后HPCC的安定性良好。A castable high-performance carbonatable concrete(HPCC) was designed based on the optimized packing design of the material system. In HPCC, a steel slag powder was the main binder, a small amount of hydraulic ordinary Portland cement was used to provide the mould-stripping strength and silica fume was added to improve the compactness of the system. Effect of carbonation curing on the mechanical properties and microstructure of HPCC was investigated. The results show that the compressive strength of HPCC after 1-d seal curing is 5.2 MPa, and the compressive strength of HPCC after pre-drying and 24-h carbonation curing reaches almost 90 MPa. A proper pre-drying is beneficial to the carbonation reaction, and the optimal moisture loss rate is 74.4%. Calcium carbonate crystals formed due to carbonation reaction are mainly calcite with a trace amount of aragonite. This leads to a further densification of the matrix, which accounts for the high strength of HPCC. In addition, the soundness of HPCC is also improved after carbonation.

关 键 词：钢渣 碳化 高性能可碳化混凝土 抗压强度 显微结构 

分 类 号：TU528[建筑科学—建筑技术科学]