Then the mixer was started, the HRWR dosage was gradually added, and the wet mixing was conducted for 3 min.
The dosages of HRWR were fixed based on the saturation dosages.
The flow spread of the mortars at HRWR saturation dosages varied in the range of 238-317 mm, which generally suggests an excellent flowing ability of SCC possessing a slump flow of 550-850 mm (Jin and Domone 2002; Safiuddin et al.
The HRWR molecules impede the attachment of entrained air-voids onto the binding materials by reducing the attachment sites (Khayat and Assaad 2002).
Also, the aeration effect of polycarboxylate-based HRWR was not pronounced in SCC mixtures, as understood based on the results of concrete air content test.
The air content of the mortars increased with the increase in AEA dosage due to the formation of more air-voids, and decreased with lower W/B ratio and higher RHA content because of the increases in binder content, binder surface area, and HRWR dosage.
The AEA dosages for achieving a target concrete air content increased with lower W/B ratio and greater RHA content due to the increases in binder content and surface area, and HRWR dosage.