Show how various Superpave tests used to characterize the asphalt binder are related to pavement performance.

The following figure shows concrete pavement with the layer thickness and elastic modulus as indicated. Assume modulus of rupture of 650 psi, load transfer coefficient of 3.2, serviceability loss from 4.5 to 2.5, and drainage coefficient of 0.9. The bedrock depth and loss of support is not considered for the subgrade. Use the design equation or monograph with 50% reliability to solve the following: 1) Determine the number of ESAL that the pavement can carry before failure. 2) If the daily traffic has 1080 single axles (20-kip), 400 single axles (24-kip), and 680 tandem axles (40-kip), and the annul traffic is the same over the design period, how many years would the concrete pavement last before failure? 8-inch Portland Cement Concrete Ec=4×106 psi 8-inch Granular Subbase Ec=30,000 psi Subgrade Mr = 5000 psi

The elastic modulus of mid-range aggregate asphalt pavement is 480 MPa while its subgrade has an elastic modulus of 55 MPa. What is the stiffness factor of the flexible pavement? 0.12 0.61 0.34 0.49

How can we improve Moisture Susceptibility of asphalt?   What are the main reasons of asphalt collapse? What is the desired air content of asphalt? What are the problems with higher air contents? Whatare the issues with lower air contents?