The first year AADT on a six-lane interstate highway located in an urban area is expected to be 10,500 in one direction. The growth rate of two-axle single unit trucks 10,000 lb/axle is expected to be 5% per annum during the first five years of the pavement life and will increase to 6% per annum for the remaining life of the pavement while the growth rate for all other vehicles is expected to be 4% per annum throughout the life of the pave- ment. Determine the design ESAL for a 20-year design life.

The projected vehicle mix during the first year of operation is:

Passenger cars (1,000 lb/axle) 83%
Two-axle single-unit trucks (10,000 lb/axle) =10%
Two-axle single-unit trucks (12,000 lb/axle) =596
Three-axle single-unit trucks (14,000 lb/axle) =2%
Pi= 3.5
pl =2.5
fd =0.7
Assume SN =4