- Author
-
Blaine, R. L.
|
Arni, H. T.
|
DeFore, M. R.
- Title
- Interrelations Between Cement and Concrete Properties. Part 3. Compressive Strengths of Portland Cement Test Mortars and Steam-Cured Mortars. Section 8. Compressive Strength of Steam-Cured Portland Cement Mortars.
- Coporate
- National Bureau of Standards, Washington, DC
- Report
-
NBS BSS 008,
April 1968,
32 p.
- Keywords
-
cements
|
concretes
|
compressive strength
|
portland cement
|
chemical composition
|
curing agents
- Identifiers
- steam-cured cements; mortars; steam curing; trace elements
- Abstract
- The relationships between the chemical and physical characteristics of 161 portland cements and the compressive strengths of 2-inch mortar cubes made from those cements after both low- and high-pressure steam, as well as moist-air curing, were studied by computing multivariable regression equations with the aid of a digital computer, and determining which of the independent variables appeared to have a significant relationship to the compressive-strength values. An increase in C3A, SO3, and K2O each appeared associated with higher compressive strengths with the low-pressure-steam-cured specimens but not with 28-day strengths of the 23 deg C moist-air-cured specimens. Increases of C3A, C3S, C2S, SO3 and fineness were all associated with higher strength values when autoclave curing was started after 5 hours, but when started after 24 hours, variations of neither C3A nor C3S appear to have any effect. The use of certain of the trace elements in the equations together with commonly determined variables resulted in a reduction in variance although the coefficients of the individual trace elements were, in most instances, not highly significant.