Limiting values for temperature differentials to control early age thermal cracking of concrete

Abstract

Early age thermal cracking due to temperature differential is one of the major issues related to mass concrete construction. Temperature differential is created due to heat of hydration of cement and heat loss from the surface. If induced tensile stresses due to temperature differential exceed tensile strength of concrete, concrete tends to crack. Current practice in the local construction industry is to limit the temperature differential to 20ºC irrespective of the grade of concrete. A Finite Element Model (FEM) was developed using ANSYS to predict early age thermal stress behavior and to propose limiting value for the temperature differential for different grades of concrete. An analytical method was also considered to obtain the limiting values for temperature differentials for different grades of concrete.