PG Grade Selection• Low Pavement Design Temperature

– Tsurf - 0.859 Tair + 1.7

• Tair = 1 day minimum air temperature

– Note: currently under review

• High pavement Design Temperature

– T20mm = (Tair-0.00618Lat2 + 0.2289Lat + 42.2) x

(0.9545) - 17.78

• T20mm = high design temp at a depth of 20 mm

• Tair = 7 day average high air temp

• Lat - geographical latitude in degrees

PG Grade Selection