The Bristol International Raceway was originally constructed in 1961. It is a sanctioned raceway of the National Association for Stock Car Auto Racing (NASCAR) and is considered to be the “world’s fastest half-mile speedway” with average speeds exceeding 190 kph. The track is 860 m long, varies between 12.2 to 21.3 m wide and incorporates 36 degree banked turns. The high bank turns are the steepest in motorsports and provide some of the most exciting competition in all of auto racing. The track configuration results in one of the most demanding facilities for both driver and machine.
The original track was constructed of asphalt. This material performed adequately in the early years, when average speeds were under 160 kph. As speeds increased over the years, the asphalt became a major problem in the turns. The asphalt would break up resulting in unsafe conditions and loss of traction.
After several unsuccessful attempts to resurface the track with various asphaltic designs, the innovative track owner decided to investigate a concrete alternative. VSL was retained to evaluate the feasibility of an oval concrete overlay. The design would necessitate continuous prestressing and the elimination of any expansion joints. The proposed design concept was accomplished through a combined team effort involving input from several local VSL branch offices in the US and the VSL Group Engineering and Development office in Berne, Switzerland. The design utilized the VSL Monostrand System along with welded wire fabric. Upon acceptance of the design concept, VSL was awarded a contract for the design, fabrication, installation and stressing of the Monostrand System, and the supply and installation of all conventional reinforcing. An ambitious construction schedule allowed only 42 days between the issuance of the contract and the completion of the concrete overlay for required tire testing. The key structural details and construction procedures required to meet design goals and schedules are listed below.