One of the main differences between testing in a laboratory and testing and casting on-site is the application of releasing agents on the equipment in the second case. On the other hand, the influence of demoulding oil on the rheological properties of fresh self-compacting concrete is currently unknown. In this way, a research project has been developed in order to investigate the influence of demoulding oil on the yield stress, viscosity and shear thickening behaviour of SCC. The rheological properties of 10 SCC mixes have been measured with the Tattersall Mk-II rheometer, after elimination of the disturbing influence of thixotropy and structural breakdown. Within the time frame measured, it is shown that loss of workability does not influence the conclusions of this paper. From the measurements, it can be seen that adding oil reduces and even eliminates shear thickening behaviour in fresh SCC, which is an advantage during fast flow conditions. On the other hand, the yield stress increases due to oil additions, which can lead to improper filling of the formwork, and possibly to air bubbles at the formwork - concrete interface.
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