Hans Brink and Associates cc, the specialists in Ultra Thin Reinforced Concrete Roads (UTRC), pride themselves in bringing a stronger, more economical and maintenance free solution to road construction by specializing in revolutionary and effective road design methods.
Thin concrete pavement technology is increasingly proving a solution for the problems South Africa is facing in terms of provincial and urban road construction and maintenance. UTRC is a relatively new construction method for urban and rural roads, replacing both the base layer and the conventional bituminous surfacing. The UTRCP consists of a 50 mm layer of 30 MPa concrete, with reference 200 welded mesh reinforcing, placed in the centre. The concrete pavement is constructed continuously, in strips of 2 m to 6m wide, with anchors at both ends of a straight section. Since there are no transverse expansion joints, as for conventional concrete pavements, the problems with failures at these joints are eliminated.
Benefits of UTRC
The continuous concrete layer may be compared to a stretched sheet of material, tied in at both ends. Because a substantial amount of the wheel load is taken up as tensile forces in the reinforcing, resulting in considerably less of the induced load being transferred to the underlying layers. The effect is that much less supporting layers are needed, with this construction method, compared conventional road construction, to achieve the same resistance to heavy truck traffic over the normal design life of the road.
The effect of spreading the load over a much larger area of the lower layers, due to the continuous reinforcing, is that even on a weak spot in the underlying road layers due to water ingress etc., the chances of pothole developing is much less likely. In fact the first experimental roads built by the CSIR did crack, but after many years of heavy traffic, still have not formed potholes.
The lessons learned in these early stages, have been well addressed and tested on many large sites, where UTRC has been used extensively with very good results, see gallery. Compare this with conventional roads in South Arica, especially provincial roads, where potholes has become a major problem.
Even with very little or no maintenance, the concrete roads will outlast any bituminous road, as the concrete will not deteriorate as bitumen are subjected to, unless resealed every 7 to 10 years. (Note that the concrete road between Vryburg and Stella has been in service for over 70 years, using very old concrete road technology.)
With the substantial amount of knowledge gained over the last few decades, we believe the UTRC roads may last even longer, while giving excellent service, with the minimum of maintenance.
This construction method has been developed by Adrian Bergh at the CSIR over the past 14 years. During this time many trial sections have ben built all over SA, with the assistance of Gautrans, City of Tshwane, Sanral, the former Cement and Concrete Institute, and many others. Some extensive testing by Gautrans’ using the heavy vehicle simulator (HVS), indicated that these roads were extremely robust, taking more than three-million E80’s (standard axle load), without failure.
A further application that has been tested successfully by the CSIR is the use of 50 mm UTRC for houses, replacing both the floor and the foundation.