- Author
- Blaine, R. L. | Arni, H. T. | Evans, D. N.
- Title
- Interrelations Between Cement and Concrete Properties, Part 4. Shrinkage of Neat Portland Cement Pastes and Concretes. Building Science Series.
- Coporate
- National Bureau of Standards, Washington, DC
- Report
- NBS BSS 015, March 1969,
- Keywords
- concrete, shrinkage | cements, chemical
- Identifiers
- portland cements
- Abstract
- The relationship between cement properties and drying shrinkage of partially hydrated neat cement pastes of normal consistency made of a large number of portland cements of different types and composition were studied by fitting multivariable regression equations with the aid of a digital computer. The time of cracking of annular specimens restrained from shrinking by a steel core varied from 0.1 to more than 40 hours. The principal variables which appeared to have the greatest effect were the fineness and K2O and C4AF contents of the cements. The fineness and K2O contents of the cements appeared to have the greatest effect on the nonrestrained shrinkage of prisms at the time of cracking of the annular specimens. The shrinkage of neat cement bars after 1, 6, 27 days, and 6 months in laboratory air differed greatly with different cements. The principal variables appeared to be the C3A, SO3, and C3A/SO3 ratios. Other commonly determined variables were associated with each of the above test values. The trace elements, other than Na2O and K2O, were not generally associated with the shrinkage or cracking characteristics. (Author)