Director of Technical Services, Florida Rock Industries, Inc., Jacksonville, FL
Pages: 19 Published: Jan 1985
Field test reports from seven major projects representing 1336 individual tests were evaluated for the effect of hot weather conditions, including the effects of placing temperatures of up to 37°C (99°F) on the 28-day compressive strength of set retarded concrete. The information was based on reports from independent agencies the concrete in behalf of the owner of the project. For the majority of the projects, the test specimens had been left exposed to ambient conditions during the initial curing period at the site. The concrete was supplied by different producers to power plant, high rise, mass transit, or highway projects in Florida and Atlanta, Georgia. The data were analyzed for temperature-strength relationships and for significant differences in average strength and standard deviation between data groups of concrete placed at temperatures below and above 32°C (90°F). The statistical analysis revealed the absence of a significant correlation between the placing temperatures and the strengths and of significant differences in the average strength and standard deviation of concrete of lower and higher placing temperature. Exceptions to these observations showed a more favorable performance in concrete of higher placing temperature.
admixtures, cement composition, compressive strength, concrete, correlation analysis, curing, field tests, hot weather, scatter diagram, set retarder, standard deviation, statistical evaluation, temperature
Paper ID: STP34209S