背散射电子图像法分析玻化微珠对加气混凝土的改性机理

作为粉煤灰加气混凝土的主要产物,托贝莫来石晶体量的变化对加气混凝土的强度、干密度和保温性能有一定的影响。通过对普通灰加气混凝土和玻化微珠改性灰加气混凝土BSE图形的分析处理,计算出两种混凝土中晶体和胶体的体积率,发现玻化微珠改性灰加气混凝土的胶体是普通灰加气混凝土的1. 5倍。结合SEM照片分析可知改性后的加气混凝土中托贝莫来石晶体变小,孔隙分布均匀,从而改善了加气混凝土的保温性能。分析结果从微观上解释了玻化微珠对加气混凝土的改性机理,而图像法则为水化产物的定量分析提供了科学依据。

Backscattered Electron Image Analysis of the Modification Mechanism of Vitrified Microspheres on Aerated Concrete

As the main product of fly ash aerated concrete, the change of crystal quantity of tobermorite has certain influence on the strength, dry density and thermal insulation performance of aerated concrete. By analyzing and processing the BSE pattern of ordinary gray aerated concrete and vitrified microbead modified ash aerated concrete, the volume fraction of crystal and colloid in two concretes was calculated. It is found that the colloid of vitrified microbead modified ash aerated concrete is 1. 5 times that of ordinary aerated concrete. Combined with the SEM photo analysis, it can be seen that the tobermorite crystals in the modified aerated concrete become smaller and the pore distribution is uniform, thereby improving the thermal insulation performance of the aerated concrete. The analysis results explain the mechanism of vitrified microsphere on aerated concrete from the microscopic point of view, while the image rule provides a scientific basis for quantitative analysis of hydration products.