Measurement and Prediction of Thermal Conductivity of Cement Paste

A model is developed that predicts the effective thermal conductivity of cement paste. It is based on a lumped parameter model, which considers both the porosity and degree of saturation of the cement paste. Existing relationships are used to compute the porosity and degree of saturation based on the water-cement ratio (w/c) and the relative humidity. The model is calibrated for oven-dry cement paste and the data closely matches values reported in the literature. As the w/c increases, the thermal conductivity of the cement paste decreases due to the addition of pore space. Additionally, predictions are made for fully saturated cement paste. Experimental values for the thermal conductivity were determined using the flash method. The results indicate that a lumped parameter model can be used to predict the effective thermal conductivity of cement paste.