硫铝酸盐水泥砂浆界面过渡区的改性

INTERFACIAL TRANSITION ZONE MODIFICATION OF SULPHOALUMINATE CEMENT MORTAR

主要研究了硫铝酸盐水泥砂浆–集料间界面过渡区(interfacialtransitionzone,ITZ)的改性对混凝土性能的影响。细硫铝酸盐水泥颗粒被预先包裹在集料表面以降低ITZ的厚度和连通情况,提高混凝土的抗压强度和抗渗性。通过建立数学模型计算细硫铝酸盐水泥颗粒的质量。利用扫描电镜、压汞仪等分析ITZ的结构组成。结果表明:进行集料预包裹可以降低硫铝酸盐水泥砂浆混凝土的孔隙率,提高混凝土的抗压强度和抗渗性;ITZ中的主要水化产物是水化硫铝酸钙。

The effects of the interfacial transition zone （ITZ） of sulphoaluminate cement mortar on the properties of the mortar were studied. In order to improve the strength and impermeability of concrete, the surfaces of aggregates were coated with fine cement particles before the concrete was mixed, which decreased the thickness and the connectivity of the ITZ. The quantity of fine cement particles were calculated approximately with mathematical models. The structure of ITZ was studied by scanning electron microscope, merecery intrusion porosimetry. The results indicate that the pre-coated aggregates decrease the porosity and improve the compression strength and impermeability of sulphoaluminate cement mortar. In addition, ettringite is the main hydration product in the ITZ.