Numerical prediction of early age concrete temperature via 3D finite difference simulation

Cement hydration is an exothermic reaction. It leads to increase in temperature and creates temperature gradients inside concrete structures during early ages. Extremes of such scenarios cause cracking of concrete and, therefore, affect the structural integrity and durability. Hence, prediction of temperature development of the concrete interior is vital in order to identify appropriate temperature control mitigation measures. However, it remains a challenge because, on the one hand, the governing thermal equations do not have closedform solutions, and on the other hand, the thermal behaviour of concrete is influenced by numerous factors, including heat evolution, heat conduction/convection, boundary conditions, etc. One possible solution is to implement numerical modelling via finite element (FE) or finite difference (FD) approaches. Amongst the two approaches, the former has a better simulating capacity to deal with complex problems, whereas the latter is relatively simple and less expensive. In this light, this research expanded an existing 2-dimentional FD temperature prediction tool towards a 3-dimentional (3D) model in view of enhancing the prediction accuracy of the 2D version. The 3D model was validated for three distinct experiments, and the prediction accuracy was found to be notable where the maximum temperature prediction offset was below 2.2 %. Then, the significance of using 3D FD temperature modelling for cube shape concrete structures and for pipe-cooled concrete structures was highlighted.