ASTM Sets Requirements for Rapid Hardening Hydraulic Cements
October 1, 2009 // Published as a news service by IHS
ASTM International published ASTM C1600/C1600M - Specification for Rapid Hardening Hydraulic Cement, which covers paving, construction, stucco, mortar and block.
Rapid hardening hydraulic cements are used in a variety of applications in which reduced cementitious contents are desired or early service is needed.
ASTM C1600/C1600M was developed by Subcommittee C01.13 on Special Cements, part of ASTM Committee C01 on Cement.
According to James K. Hicks, chair of C01.13, four types of cement are covered by ASTM C1600/C1600M:
- Type URH - ultra rapid hardening, for use where ultra high early strength is desired.
- Type VRH - very rapid hardening, for use where very high early strength is desired.
- Type MRH - medium rapid hardening, for use where mid-range rapid hardening, high early strength is desired.
- Type GRH - general rapid hardening, for use when the higher strength properties of Type VRH or Type MRH cement is not required.
"ASTM C1600 lists minimum requirements for compressive strength, setting time, shrinkage and soundness (autoclave expansion)," said Hicks. "Optional specifications for sulfate expansion, alkali silicate reactions with aggregates, heat of hydration and expansion in water are also listed."
Hicks said ASTM C1600 cements that require calcined clinker typically use much less heat and evolve less carbon dioxide than other forms of clinker production.
"Some C1600 cements are made principally from coal combustion products, thereby requiring no additional fuel use evolving no additional carbon dioxide," said Hicks.
Source: ASTM International.