ABSTRACT
Chapter 5 has introduced the analysis tools which allow the calculation of stress levels in concrete under load. Earlier, in Chapter 4, the concept of fatigue life was presented, potentially allowing a level of tensile stress to be selected, a certain proportion of the ultimate tensile strength, in order to permit a certain number of stress applications (i.e. wheel loads) to be carried. In theory, therefore, it is now possible to carry out a fully ‘analytical’ pavement design using ‘mechanistic’ principles. Unfortunately, however, the point has been made on numerous occasions
that there is no one agreed approach which provides accurate results for all design cases. Furthermore, the inevitable variability in concrete properties on even the best controlled site has been clearly illustrated. Add to this the equally inevitable variability in slab thickness and foundation stiffness, together with uncertainty in future traffic loading, and it is clear that pavement designs should not be based simply on straightforward analysis of idealised cases. This chapter and the next will therefore address the practical problems
associated with real concrete pavement design. This chapter will cover traffic characterisation, pavement foundations and the issue of design reliability; the various practical concrete pavement design methods available will be presented in Chapter 7.
