Nine Questions Exam (Note: please keep your answers brief but pertinent. You may use any resources you can find for your answers)

1. In AASHTO 1993 Pavement Design Guide, is a mix of axle configurations and loads converted to the Equivalent Single Axle Load (ESAL) in the same way for flexible pavements and rigid pavements (2 points)? Does Florida Department of Transportation (FDOT) use different ESAL conversion factors for flexible and rigid pavements (2 points)? If you are allowed to use a general 4th power law for ESAL conversion in the design of a gravel pavement, how many ESALs are 1000 repetitions of a 20 kN single axle load equivalent to (4 points)?
2. For an asphalt binder PG 76-22 that is commonly used in Florida, what do “PG”, “76” and “-22” mean (3 points)? Is it an unmodified binder or modified binder (2 points)?
3. In AASHTO MEPDG, how are the rut depths calculated in various analysis time increments accumulated (3 points)? How are the fatigue damages calculated in various analysis time increments accumulated (3 points)?
4. Is a drainage layer commonly included in a conventional flexible pavement structure (2 points)? Why (4 points)?
5. In FDOT Rigid Pavement Design Manual, two typical rigid pavement structures are included: one with a 4-inch asphalt base and the other with a 60-inch special select soil subgrade. Explain the benefits of using the 4-inch asphalt base underneath the concrete slabs (6 points).
6. What is departure-to-coverage ratio (or pass to coverage ratio) (3 points)? Why are only departure flights considered in the design of runway pavement structures (3 points)?
7. Multilayer elastic theory plays a key role in flexible pavement analysis and design to estimate the critical pavement responses to external loads. Can this theory also be applied to the analysis and design of rigid pavements (2 points)? Provide justifications to your answer (6 points).
8. Assume that you are hired as a pavement engineer by a port authority to design the pavement structure(s) for several container terminal operational areas, which include the wharf, the container storage yard, and an automobile parking lot near office buildings. Will you design the same pavement structure for all these areas (1 point)? Why (2 points)? If relevant design manuals or specifications are not available, what general steps will you follow to do the pavement design (3 points)? In these steps, can you use any tools or software you have learned from this course, and if yes, for what purpose (2 points)? Can you use the AASHTO Pavement ME software or the FAARFIELD software for design without modification (1 point)? Can you use OpenPave or EverFE for pavement response analysis (1 point)?
9. Driverless semi-trucks have appeared on Florida highways. With the fast development of autonomous vehicle technologies, it is expected that more autonomous trucks will appear on highways. These trucks can be well controlled for their trajectories on the road, including their speed, spacing, lateral positions, and lateral wandering. Describe what potential impacts autonomous trucks will have on (1) flexible pavement performance, (2) rigid pavement performance, (3) flexible pavement design, (4) rigid pavement design (10 points).