Analysis of stresses in rigid concrete slabs and an introduction to concrete block paving

This chapter deals primarily with the development of stresses in rigid pavements, but includes a section on concrete block paving, as this is a form of concrete pavement that behaves in a different way from rigid concrete.

Stresses in rigid concrete slabs result from applied load and from restraint to slab movement induced by moisture loss and temperature changes. This chapter explains how those stresses are calculated and how those calculated stresses are compared with concrete strength in order to proportion slab thickness. It demonstrates the use of Highways England's (formerly the Highways Agency) transfer function equation (see Figure 2.3 of HA et al., 2006a) that relates the allowable stress to the number of repetitions of a wheel patch load on a fatigue basis. In other words, this chapter presents a mechanistic design method for rigid highway pavement slabs. In particular, pure tensile stresses and tensile flexural stresses are considered, since it is these stresses that can lead to concrete cracking and to subsequent deterioration of the pavement. Compressive stresses developed in the concrete slabs are usually so low that they can be regarded as negligible.