ABSTRACT

In this study, the sprayed concrete mix design was changed to make the concrete more pumpable and sprayable without increasing the amount of superplasticiser. This was achieved by use of an air entrainer to give good flowability and enhance pump-ability, and additionally some “slump killing” effect after placing. The effect of micro-air stability was checked by air content measurements on fresh concrete (NS-EN 12350-7) and comparison with compressive strength (NS-EN 12390-3), to find an optimal air-content for sprayed concrete. Also, the effect of air entrainment on the frost durability will be checked in later tests.