concretebasics.org: your guide to cement & concrete

Types of Cement

Ultra High Early Strength Cement

This type of cement develops strength more rapidly (not to be confused with setting time). This cement also has rapid hardening properties. Ultra High Early Strength Cement does not use any admixtures and is therefore suitable for RCC & PSC works. It is ideally suited to the pre-cast concrete industry and other structures where early age strength for stripping of formwork is required.

The rapid strength development of Ultra High Early Strength Cement is due to very high fineness of the cement: 700-900m²/kg. Because of this, gypsum content has to be higher. However, the higher gypsum content has no adverse effect on long term soundness as the gypsum is used up in the early reactions of hydration.

Ultra High Early Strength Cement reaches strength comparable to 3 day strength of Rapid Hardening Portland cement in 16 hrs & 7 day strength in 24 hrs. However, there is little gain in strength beyond 28 days.

Ultra High Early Strength Cement is marketed in U.K as SWIFTCRETE. Somewhat less fine cement is SPEED cement, developed in Belgium.