Abstract
Generally, a crack in concrete occurs by strain due to difference in thermal expansion between at the central part of the concrete and at the surface of it, and such a difference is brought from the rapid generation of heat of hydration of cement in hardening process. Then, the measurement of temperature elevation in concrete by adiabatic process is important and which is required to the quality control of it. In order to carry out the measurement of temperature elevation with higher precision and with fewer sample of concrete than those of previous one, a precision thermo controller and an improved thermostat chamber for the adiabatic calorimeter have been designed and constructed in this study. In the performance test using test piece of non-reactive material, linear temperature elevation was observed during electrical heating and which was maintained as the same temperature after stop of heating. Reproducibility and linearity in temperature elevation were estimated to be less than 0.2K and 0.5%, respectively. Adiabatic performance was believed within 0.05Kday-1.
