In this research, the finite element theory is used in place of multi-layer elastic theory, and cyclic loading is considered in place of static loading. A flexible pavement structure with a thin bituminous surfacing and a granular base is modelled as a finite element model, using a general purpose finite element computer code. A curve is developed for surface deflection versus number of load applications. Similar curves are developed, varying the thickness of the base layer. Those curves are extended, and the number of load applications required to produce a 25mm rut depth on the surface are calculated. The thickness of the base layer versus the number of load applications required to produce a 25mm rut depth, is plotted and presented as the design chart for the design of flexible pavements. The calculated deflections after various number of load applications are matched with the rut depths measured after application of corresponding number of cycles of ALF load. (Author/publisher) For the covering entry of this conference, please see ITRD abstract no. E208431.
Samenvatting