Determination of critical mechanical properties of structural lightweight concrete and the effects of these properties upon the design of the pavement structure.

1648354PDFTech ReportResearch Report Number 55-2Research Project Number 3-8-63-55Interagency Contract No. 4413-767Air contentConcrete curingLightweight aggregatesLightweight concreteShrinkageThermal expansionVolume changesCoefficient of thermal expansionUnited StatesTexasUniversity of Texas at Austin. Center for Highway ResearchHouston, James T.Thompson, J. NeilsUniversity of Texas at Austin. Center for Highway ResearchTexas. Highway DepartmentUnited States. Bureau of Public RoadsUS Transportation CollectionIn this study a comparator-type measuring system was developed to accurately determine volume change characteristics of one structural lightweight concrete. The specific properties studied were the coefficient of linear thermal expansion and unrestrained shrinkage. One finding of this report was that the coefficient of expansion of the type of lightweight concrete studied was only slightly less than that of normal-weight concrete of similar air content and cement factor. Another finding was that an increase in air content of the lightweight concrete resulted in a slight reduction in its value of coefficient of expansion. The use of the aggregate studied in this report resulted in a concrete that, in general, had a low unrestrained shrinkage as compared with concrete made with other lightweight aggregates (particularly those with higher absorption characteristics) as reported by other investigators. A study of the effect of curing conditions on the unrestrained shrinkage properties of this lightweight concrete indicated that curing procedures might be developed which could minimize destructive volume changes during the curing period