Estimation of the thermal properties of hardened cement paste on the basis of guarded heat flow meter measurements

Abstract

In the present study, a new analysis method is proposed to measure thermal conductivity, thermal diffusivity, volumetric specific heat capacity, and specific heat capacity of cement-based materials based on the guarded heat flow meter apparatus. We tested hydrated cement paste specimens with 0.4 water-to-cement ratio and applied both steady and non-steady state data to compute thermal properties of the hydrated cement paste. Thermal conductivity and thermal contact resistance were determined as 1.28 W m−1 K−1 and 0.038 m−2 K W−1 using steady state data. Furthermore, using a computerized system of heat flow meters and non-linear regression, we used non-steady state data to measure thermal diffusivity, volumetric specific heat capacity and specific heat capacity of the hydrated cement paste as 4.77 × 10−7 m2 s−1, 2685.4 kJ m−3 K−1, and 1.28 kJ kg−1 K−1. The relative uncertainties of these properties fell within 2–7% range and the residual distributions were validated to follow a normal distribution based on quantile–quantile tests.