Q2. A flexible pavement is to be designed based on AASHTOmethod. The following are the characteristics of this pavement: R =90%, S0 = 0.40, Pi = 4.5, Pt = 2.0, SN = 3.5 and Mr (subgrade) =15,000 psi. (a) If it was decided to use to a base course and anasphalt layer, what will be the thickness of each if you know thatthe sub-grade CBR = 8, base course CBR = 85, m = 1.0, surfacemodulus of elasticity = 400,000 psi. (b) How many years thispavement will approximately last, knowing that the average ESAL peryear during the design period is 530 000 repetitions.
