High-range water reducer, a chemical admixture (ASTM C494 Type F or G) that disperses cement particles so the mix can drop 12 percent or more of its water at the same slump, or keep its water and flow much farther. Polycarboxylate products can take a 3 in slump past 8 in, which makes them the backbone of SCC and high-strength mixes. The effect fades with time and heat, so some loads get their dose on site just before discharge.
Hold the truck, the HRWR goes in here and he needs five minutes on high before we chute it.
When a pumper says the load needs a shot of super, he means HRWR, not water.
Also heard as
- superplasticizer
- super
- high-range
Related terms
Admixture
A product dosed into a concrete batch, usually by the ounce, to change its flow, set time, air or durability.
SCC
Self-consolidating concrete, a highly fluid mix that fills forms and wraps rebar under its own weight.
Slump
How far a cone-shaped sample of fresh concrete sags, the standard field measure of consistency.
w/cm
Water-to-cementitious-materials ratio: the weight of mix water divided by the weight of cement plus SCMs.