The Roodekrans Trial Sections: The Role of Structural Support under Very Thin Jointed and CRC Pavements Subjected to Heavy Traffic

8-vdM SteynThe Roodekrans trial sections were constructed to evaluate the effect of aggregate interlock, dowels, continuous reinforcement and various supporting layers on the relative performance of very thin concrete pavements. The sections were constructed on the exit road from a quarry and have successfully sustained 400000 equivalent 80 kN axle loads to date. The concrete pavement thickness varied from 50mm to 140mm and the base support consisted of either a natural or stabilized gravel layer 100mm thick, or in some cases, thin asphalt between the stabilized base and slab. After 2 years of heavy truck traffic, a panel of 30 experienced road engineers visually evaluated performance and found the role played by the support conditions to be crucial for the performance of the road.

This paper summarizes the design and construction of the 10 sections and discusses their performance with specific reference to the role that the support conditions played in the good performance achieved. The findings of the reviewers are first discussed to obtain a viewpoint on the performance of the sections, followed by an analytical evaluation of the sections to arrive at some mechanistic explanations for the good performance of the sections.

The data obtained from these sections have been used in upgrading the mechanistically based design program, cncPave, that has been developed in South Africa.

Presented at the 8th International Conference on Concrete Pavements in 2005.

Authors: W J vdM Steyn, P J Strauss, B D Perrie, and L du Plessis