PP膜对表层混凝土微观结构的影响研究

Influence of Polypropylene Film (PP) on the Configuration of Cover Concrete

利用PP膜制成透水模板,进行混凝土性能实验。对实验混凝土表层取样,进行扫描电镜的观察研究。扫描电镜结果表明:了随着养护时间的延长,水泥水化逐渐完善,水化产物硅酸钙凝胶逐渐转化成水化硅酸盐晶相。同时,使用透水模板的混凝土较普通模板的表层混凝土的水泥水化产物-硅酸盐晶体致密。因此混凝土的抗渗等性能将得到相应的增加,混凝土的耐久性也将得到提高。

Controlled permeability formwork would prolong the life of concrete by changing the microstructure of cover concrete. In this paper, the controlled permeability formwork was composed of polypropylene film. The properties of the cover concrete were characterized by scanning electron microscopy （SEM）. The results of SEM demonstrate that, with time of curing elapsing, the hydration degree of cement will increase. And the silicate gel of cover concrete will transform mostly to silicate crystal. At the same time, the structure of silicate crystal is more compact in the cover concrete using controlled permeability formwork than in the concrete without using controlled permeability formwork. So the properties of resistant penetration and durability of concrete will be improved in this way.