Modeling thermal-shrinkage stresses in early age massive concrete structures - Comparative study of basic models

The hydration of cement generates heat and can subject structural elements to temperature variations that can be significant, particularly in massive concrete structures. Considerable attention has been focused on this problem dating back to the 1930s during construction of concrete dams in North America. Thermal cracking in massive concrete as well as cracking resulting from drying and autogenous shrinkage, not only forms mechanical weaknesses and cracking but also causes a reduction in durability. Therefore, prediction of the thermal-shrinkage stresses and the risk of cracking in massive concrete structures is the important engineering task. The basic models, which can be implemented for the evaluation of the thermal-shrinkage stresses, are briefly described and compared in the paper. The results of numerical analysis presented in the paper showed differences in values and distribution of thermal-shrinkage stresses predicted with different models. The analyses were performed for two types of structures: the massive foundation block as the example of internally restrained structure and the reinforced concrete wall as the example of externally restrained structure. (C) 2014 Politechnika Wroclawska. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.