硅灰预处理对高性能水泥基材料力学性能的影响及其机理  

Effect of Pretreatment of Silica Fume on Mechanical Properties of High-Performance Cement-Based Materials and Corresponding Mechanism

作　　者：林东[1] 西晓林[1] 房满满[1] 文梓芸[1] 

机构地区：[1]华南理工大学材料科学与工程学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2008年第11期138-142,146,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：粤港澳关键领域重点突破项目(2006Z43)

摘　　要：为制备高性能水泥基材料,研究了硅灰预处理对水泥基材料力学性能的影响,并分析了其机理.研究结果表明,通过对硅灰进行化学表面改性预处理,可改善掺加硅灰的高性能水泥基材料的力学性能,其抗压强度达200MPa以上,抗折强度超过30MPa.颗粒粒径分析、Aim和Goff模型计算结果表明,硅灰经过预处理后,拆散了硅灰的团聚体,改善了其在水泥基材料中的分散均匀性,增大了体系的填充率,提高了水泥基材料的密实度.SEM和XRD分析表明,对硅灰进行预处理,改善了水泥基材料中集料与水泥浆体界面过渡区的结构,从而提高了水泥基材料的强度.研究还表明,微纳米级硅灰颗粒具有极强的自团聚效应,改善硅灰的分散性是充分实现其优异的物理、化学特性的关键.In this paper, the effect of the pretreatment of silica fume on the mechanical properties of cement-based materials was discussed to prepare high-performance cement-based materials, and the corresponding mechanism was analyzed. The results show that the mechanical properties of cement-based materials improve after the pretreatment of silica fume, the compressive strength and the flexural strength respectively being more than 200 MPa and 30 MPa. Moreover, according to the calculated results obtained via the Aim-Goff model and the tested results of particle size distribution test, it is concluded that the pretreatment of silica fume disperses the agglomeration of silica fume and increases the filling index of the system, thus improving the density of the material. It is also indicated from SEM and XRD results that the pretreatment of silica fume improves the strength of the cement-based material because the structure of the interface transition zone through the dispersion of silica fume is improved. In addition, how to overcome the strong agglomeration effect and to improve the dispersion of silica fume nano-particles are the key to the full utilization of physical and chemical performances of silica fume.

关 键 词：高性能水泥 力学性能 硅灰 分散 填充率 界面过渡区 

分 类 号：TU528.571[建筑科学—建筑技术科学]