Thermomechanical analysis of early age concrete by computer modeling

Resumo

This study describes a procedure for the analysis of concrete structures where thermal properties are
investigated in a finite element model to predict the temperature and stress profile elements due to the hydration
process at early ages. An exponential function is used to determine the degree of hydration of the concrete; the
temperature-dependent thermo-physical parameters are considered, and the external heat loss by convection. The
commercial software ABAQUS was used to carry out the study and FORTRAN subroutines were developed to
allow solution-dependent material properties in the calculation of thermal stress (taking into account the rising of
Young's modulus). The main data are obtained from the literature and adjusted for this specific study, to predict
the evolution of temperature and the tensile tendency of a concrete structure in the initial hours. The numerical
results obtained in this work are well correlated with the literature values. The results show the thermal-stress
behavior of a concrete block during the early age, taking into account the variation of elasticity modulus and also
the weather conditions of Curitiba.