In mass concrete constructions, concrete at early ages experiences thermal deformations due to heat generation caused by the hydration reactions. When these deformations are restrained, stresses will develop and can lead to cracking of concrete with undesirable consequences on aesthetics and structural durability. The use of numerical models in order to foresee and prevent this problem is of crucial importance. This paper deals with the development of a finite element based numerical analysis procedure for the determination of temperature distribution due to heat of hydration within a thick raft foundation. The developed finite element program has been validated with the experimental results available in the literature. For the raft of 3 m thickness, a large variation in temperature is noted and is sustained for a longer duration during the construction phase. This information can be effectively used while designing the raft for structural as well as durability considerations and appropriate measures can be taken to bring down the temperature levels so as to avoid through cracking.

Keywords: Early age concrete, Heat of hydration, Numerical model & degree of hydration.