کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1454993 | 1509696 | 2013 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Primary particle size and agglomerate size effects of amorphous silica in ultra-high performance concrete Primary particle size and agglomerate size effects of amorphous silica in ultra-high performance concrete](/preview/png/1454993.png)
Silica fume is widely used in ultra-high performance concrete (UHPC). However, it is a by-product in the industrial silicon production and therefore far from an optimized additive. Silica fume improves the compressive strength, but its detailed reaction mechanisms in concretes with low water/cement ratios are not yet fully understood. This study focuses on the influence of primary particle sizes and sizes of agglomerates of different amorphous silicas in UHPC. As a reference system, wet-chemically synthesized silica was used with very high purity, defined particle sizes, narrow primary particle size distributions and controllable agglomerate sizes. The obtained data were compared to silica fume. The results indicate that non-agglomerated silica particles produce the highest strength after 7 d, but a clear dependence on primary particle sizes, as suggested by calculations of packing density, was not confirmed. UHPC may be improved by incorporating an ameliorated dispersion of silica e.g. through commercial silica sols.
Journal: Cement and Concrete Composites - Volume 37, March 2013, Pages 61–67