A method of controlling thermal crack for mass concrete structures: modelling and experimental study

The control of the concrete temperature to prevent cracking can be viewed as principal goal in the design and construction of mass concrete. This paper researched on a novel technique for minimizing both the difference and the peak value of the temperature in mass concrete. Following this technique, the mass concrete is divided horizontally into two parts of different concrete mixtures but having the same strength grade. While the upper part is the normal heat concrete, the lower part can be considered as the low heat concrete which generate lower hydration heat than the upper part does. The influences of (i) concrete proportions of the layers; and (ii) thickness of the upper layer on the thermal behavior in mass concrete are two important aspects of the technique. Therefore, these two points represent important objectives of our present research. For this purpose, some numerical simulations with finite element method (FEM) and an in-situ experiment on a mass concrete block were performed. As a result, the simulated temperature field was validated by comparing with the experimental result and the principles of layers' mixtures and thickness were drawn.