Abstract
Investigations on the effect of composition of the fine sand fraction on air-entrainment and on the characteristic of the air voids as a function of the waiting time before compaction of the concrete have revealed the following: Settleable solids (below 0. 063 mm) in the aggregate required about nine times, and sand in the 0. 063-0. 125 mm size fraction required about three times, as much air-entraining agent as the 0. 125-0. 25 mm sand fraction. The required amount of air-entraining agent depended also to a significant extent on the water requirement of the sand and thus not only on its granulometric composition but also on its mineralogical features, particle shape and surface roughness. For a fine sand content of 11. 3 per cent (by volume) of the sand it was necessary to add about 20-55 per cent more air-entraining agent than for a fine sand content of 5. 9 per cent.
| Translated title of the contribution | Air-Entrained Concrete - Recent Investigations on the Fine Sand Composition, Waiting Time Before Compaction, and Redosing of Air-Entraining Agents. |
|---|---|
| Original language | German |
| Pages (from-to) | 742-748 |
| Number of pages | 7 |
| Journal | Betonwerk und Fertigteil-Technik/Concrete Precasting Plant and Technology |
| Volume | 53 |
| Issue number | 11 |
| State | Published - Nov 1987 |