Abstract:
Accurate numerical modelling of the behaviour of road pavement layers is an important
requirement for the design and evaluation of road pavements. This modelling includes the
prediction of pavement performance under the action of traffic loading and environmental
factors. Depending on the complexity of the models, properties of pavement layers that may
be considered are wide-ranging – from linear or nonlinear elastic to cross-anisotropic through
to linear visco-elasto-plastic. Some properties, such as cross-anisotropic, are not only related
to placement and compaction of the pavement layers, but are also inherent to the materials
used. Other properties, such as linear visco-elasto-plastic, are specific to asphalt concrete
and depend on the speed and magnitude of traffic loading, as well as the environment
(temperature) in which the road is located. This paper presents basic theoretical derivation of
numerical modelling of a flexible pavement considering cross-anisotropic material properties
(with isotropic properties as a special case). The solutions derived in this paper are based on
Hankel transformation of Navier’s equations. The accuracy and validity of the solutions are
verified through comparisons with a proprietary finite element method (FEM) package. For
this purpose, a pavement structure composed of five main layers constituted by isotropic and
cross-anisotropic (also known as transversely isotropic) material properties is analysed. In order
to vary some of the layer properties with depth, the main layers were sub-layered, resulting in a
17-layer pavement system.
Description:
This research study was part of the revision
of the SAPDM, a project sponsored by the
South African National Roads Agency SOC
Ltd (SANRAL) and the Council for Scientific
and Industrial Research (CSIR).