Austin a step closer as asphalt goes down

The Circuit of the Americas in Austin is beginning to take shape following the application of the first layer of asphalt on Tuesday.

Whilst it's believed construction remains behind schedule following heavy rainfall during the tail-end of 2011, application of the first of three layers of asphalt is promising.

The unique formula has been developed especially for the climate and region, according to Dr. Rainer Hart of Hart Consult International which has worked with Hermann Tilke on various F1 circuits.

"We don't have any general race track mix design," Dr. Hart explained to the Circuit of the Americas website. "A mix design has to be created for each track individually regarding climates, local standards, availability of suitable aggregates and bitumen.

"The quality of the aggregates is better compared to usual roads regarding resistance against polishing. The asphalt has special requirements and modifiers."

The final layer won't be laid until a month before the event takes place in November to avoid damage from construction machinery.