Title: Long-Time Study of Cement Performance
in Concrete Chapter 9-Correlation of the Results of laboratory Tests with Field Performance Under Natural Freezing and Thawing Conditions
Author(s): F. H. Jackson
Publication: Journal Proceedings
Appears on pages(s): 159-194
Keywords: no keywords
Summarizes and evaluates the results of laboratory tests spanning 14 years of the Long-Time Study cements and concretes containing them and field tests up to 12 years of concretes containing the same cements. Many of the field installations, although subject to severe exposure, have not weathered sufficiently to allow comparisons. Of the three permitting appraisal the only positive conclusion that can be drawn now is the superior performance of air-entraining cements. Laboratory freezing and thawing tests of concrete correlate well with field performance in showing the markedly improved durability of air-entrained concretes. Tests at two laboratories and at two of the field installat,ions give some indications, clouded by many inconsistencies, that Type IV cement concretes are somewhat more frost resistant than concretes made of other types of cement, However, this trend is not indicated by other investigations which show quite conclusively that damage by freezing and thawing is a physical matter and is not influenced by the chemical composition of the cement. An over-all appraisal of the results of the Long-Time Study tests to date indicates that, of the many physical tests made of the LTS cements, only the test for air content is of any value in indicating relative resistance to freezing and thawing.