Modeling of Slab–Foundation Friction in Jointed Concrete Pavements under Nonlinear Thermal Gradient or Traffic Loads

Abstract

The accurate modeling of the thermomechanical response of jointed concrete pavements is of primary importance in the design of pavement sections. From the initial development of pavement analysis software in the early 1970s, it was recognized that the finite element method was the most appropriate modeling tool because of its potential ability to capture all pavement response features. A series of software development efforts have culminated in the production of NYSLAB, an analysis tool for jointed pavement that can predict the complete thermomechanical response, including pavement curling and interactions between slab and foundation. A series of studies were developed in NYSLAB specifically to look into slab–foundation friction generated by nonlinear thermal gradients and traffic loads. Nonlinear temperature gradients can produce slab expansion and contraction that lead to frictional traction between slabs and foundation. The prediction of these friction tractions is complicated by the curling of the slabs that cause some portions of the slabs to lose contact with the foundation. The results of the studies highlight the importance of considering these frictional tractions in the analysis of jointed concrete pavements because they have a significant impact on the bending stresses of portland cement concrete slabs.