水泥基材料界面过渡区（ITZ）结构属性与界面干扰的试验研究

Experimental Study on Structural Characteristics and Interference Effects of Interface Transition Zone (ITZ) of the Cement-based Materials

总结与归纳了国内外近20年以来有关水泥混凝土界面过渡区(ITZ)的最新研究成果,并进一步阐述了ITZ形成机制与生成特点,提出了在水泥水化反应的早期微生成物具有大晶体优先(PBC)、大界面着床(CAI)与晶体外扩(CE)等三大属性。为了达到改善水泥基复合材料性能的目的,针对ITZ微环境,提出了表面能干扰和键能控制两大机理。首次提出了“氢键能”与“反氢键能”概念来阐述对水分子的干扰机理,通过抑制CH与AFt晶体优先生长与晶体着床属性,来削弱其生长发育,在空间和时间上使之有更多的C-S-H凝胶物质生成。研究试验中采用烷烃类非极性基团因子,并借助硅氧键Si-O,对集料表面进行修饰,形成低表面势能,使之产生干扰效应,从而实现阻滞或消除ITZ微环境的形成。通过对水泥砂浆试件的实验结果表明:干扰砂浆与普通砂浆相比,28 d抗压强度提高了67%,28 d抗折强度(替代法)提高了11%,干扰砂浆试件的吸水率降低了75%左右。根据干扰实验研究成果,对于水泥基材料的几个相关问题与概念提出了新的认识。

In this paper,the latest research results with regard to the Interface Transition Zone(ITZ)of cement concrete in twenty years are summarized and induced,the forming mechanism of the ITZ and its developing characteristics are furtherly expounded,and three properties of the micro-products in the early period of hydration are put forward which are a first priority bigger crystallogeny(PBC),crystal adhered to large interface(CAI)and itself crystallizing extrapolation(CE).In view of the ITZ micro-environment,two mechanisms of surface energy interference and bond energy control are put forward to improve the properties of cement matrix composites.The concept of hydrogen bond energy and anti-hydrogen bond energy is first proposed to describe the interference mechanism for water molecular.The inhibition of the CH and AFt growth of large crystals and its implantation properties weakens its growth and generates more C-S-H gelatinous in time and space.In the experimental study,the non-polar group factors are used to modify the aggregate surface property by means of the polar of Si-O to form low surface potential energy and interference effects to block or eliminate the formation of the ITZ micro-environment.The experiment of cement mortar shows that the compressive strength of the specimen after 28 days increases 67%after the interference,the shear strength increases 11%,and the water absorption decreases about 75%.According to the results of the interference experiment,new cognition about cement-based materials are put forward for several questions and concepts.