President, Kiln Technology, Inc., Allentown, PA
A survey of portland cements marketed in North America was conducted in 1994 under the sponsorship of ASTM Committee C-1 on Cement. The primary purpose of the survey was to provide modern data on cement characteristics and to aid C-1 subcommittees in evaluating standard development needs. The last previous survey of similar scope was done by the National Bureau of Standards on cements procured in 1953 and 1954, with the data published during the period from 1965 through 1971 (Clifton and Mathey 1971; Blaine et al. 1965). The NBS survey differed in scope by including large amounts of testing data on concrete.
The current survey includes 387 different cements, with cements from 136 of the 140 cement-producing facilities in the United States and Canada plus several foreign cements from import terminals. The data show that modern cements differ from those produced in the 1950s, with differences in compositional and physical characteristics clearly in evidence, thus making obsolete the classification of types used in the previous survey. While an overall classification into five basic types is still applicable, the conceptual definitions of those types have changed in several respects, and there now are numerous subtypes not previously given officially recognized status.
It is expected that this snapshot of modern cement characteristics will assist ASTM committees in their development of standards relating to portland cement and may provide a basis for consideration of many topics relating to hydraulic cements.
Paper ID: CCA10140J