Thermal stress analysis of jointed plane in concrete pavements

Abstract

Daily changing temperature causes significant thermal stress and deformations in concrete pavement with laterally fixed planes. These stresses are important parameters included in dimensioning of pavement and are significantly depended on thermal difference of plane (i.e. difference in temperature between upper and lower surface plane). In this article, thermal stresses were analysed in relationship to different diameters of dowel bars. First of all, the studies were focused on stresses distributed around the dowel bar and caused by thermal differences. The analyses were carried out using finite element method (FEM). Based on this model, temperature distribution in concrete slab was studied and next calculations for different types of dowel joints and various climatic conditions in Central Europe (Poland) were performed. Results showed that application of dowel bars with small diameters increases stresses around them. Especially harmful is concentration of stretching stresses in concrete on two sides of dowel bar. These stresses can exceed permissible values in the case of incidental strong thermal differences. The obtained results can be helpful in design of new concrete pavements and assessment of their load in countries with big temperature amplitudes.