Laboratory test procedures to predict the thermal behaviour of concrete.

[摘要] The cracking of mass and structural concrete due to thermal stress is a major problemin the concrete construction industry. Concrete will crack when the thermalstress exceeds tbe tensile strength of the concrete, Decisions on the type of concretemix, cooling facilities and construction techniques to be used in the erection of aconcrete structure can only be made if the thermal behaviour and strength of theconcrete can be predicted during hydration. This thesis describes the developmentof a low cost, computer controlled, adiabatic calorimeter to determine tlte heat ofhydration and a probe to determine the thermal conductivity or concrere samples.The main thrust of this thesis is the development of the thermal conductivity probewhich, for the first time, can measure the thermal conductivity of concrete throughall stages of hydration. A thermal model was also developed to verify the results,and the use of the calorimeter for temperature matched curing tests is also discussed.Results, obtained from the test procedures described, will provide far more accuratepredictions of the temperatures in concrete structures than was possible in the past.

[发布机构] University of the Witwatersrand