Influence of supporting base characteristics on shrinkage-induced stresses in concrete pavements

This paper presents an analytical model for prediction of shrinkage-induced stresses and displacements in concrete pavements due to the restraint of the supporting base. The model relies upon the interfacial friction stress transmitted between the slab and base as the fundamental mechanism of restraint provided by the base when concrete shrinks. By analyzing experimental results reported in the literature, a bilinear relation describing the friction stress-slippage behavior of the slab/base interface is adopted in the model. Closed-form expressions of shrinkage stresses and displacements in the concrete slab are obtained. The model quantifies the effects of concrete properties and the interfacial characteristics of the concrete slab and base on the shrinkage stresses and displacements. By applying the slab/base frictional stress-slippage relation of seven typical supporting bases in the model, the influences of the supporting base on the development of shrinkage stresses and displacements in the concrete slab are investigated. In addition, the effect of "bond breaker" layers on the shrinkage stresses in the concrete slab lying on a hot mix asphalt concrete base is studied with the model.