Experimental investigation of thermal properties of concrete

Abstract

In order to investigate the response of hardened concrete structures to thermal loads, specific heat capacity and thermal conductivity of hardened concrete and heat transfer coefficients between concrete and different formwork materials were investigated. Specific heat capacity and thermal conductivity values were determined by using an innovative transient measuring technique based upon linear heat source theory. Tests were conducted experimental setup developed and values were derived based on simplified theory of the linear heat source developed by Carslaw and Jaeger. Specific heat capacity values were evaluated against mix proportion of concrete and thermal conductivity values were determined with the age of selected mixes. Heat transfer coefficients were determined by simulating the temperature results obtained from experimental investigation with finite element modelling using ANSYS software. It was found that specific heat capacity of concrete increases with water/cement ratio and aggregate volume percentage in the mix. Thermal conductivity of concrete was found to be decreasing first few days and thereafter increasing to a constant value. A method to determine the heat transfer coefficient between concrete and different formwork types under various environmental conditions was developed.