# Fundamentals of Transportation/Design/Additional Problems

## Additional QuestionsEdit

1. For the autobahn in Germany are the roads designed with a high design speed or do they let people operate above the design speed? Yes
2. Are AASHTO guidelines law? Not as such, though it is considered state of practice, each state DOT adopts them independently, so when new guidelines are developed, state may still be using older documents. However, not adhering to engineering practice without good reason may be grounds for a lawsuit against the state (the state willing).
3. Is state DOT liable for accidents occurring due to roads not being wide enough? Potentially.
4. Are vertical curves or horizontal curves used more often in highway design? (I don’t know, I suspect vertical, since streets are often in a grid).
5. If the largest vehicle uses the road once a year, do we consider it a design vehicle. Probably not, it would generally be easier to note it as a wide vehicle or a long vehicle, or a tall vehicle…
6. Has road heating ever been considered for ice repellent in cold regions? Yes, but costly, risk of breakdown in heating system … would require breaking road to repair. Done in some places (driveways, sidewalks, ramps, bridges). Typically Europe or Japan, don’t know of US road applications. Some commercial firms, e.g. Mechaheat do this.
7. Does the change in slope of a vertical curve have a large effect on the coefficient of friction? (As the slope changes there has to be a change on the vertical force on the car)
8. How does the coefficient of friction come into play while designing the downslope of vertical curves?
9. What is right-of-way
10. Give six functions/advantages of medians.
11. What is the difference between roadside barriers and median barriers Why are they used?
12. What is the difference between design speed and running speed?
13. What are lane widths for arterials and two-lane roadways?
14. Draw the cross-section elements in a highway design?
15. Common cross slopes for roadbeds are usually measured at ___ degrees.
16. What are the types of side slopes? What is their function?
17. What are the two distinct functions of streets and highways: movement and access. What are the functional classes of roads (name 3).
18. What book is considered to be the bible of highway design?
19. What are curb cut controls on highway or freeway?
20. When is a guard rail implemented?
21. Give 9 factors influencing highway design?
22. Why is sloping the road important? What does it prevent?
23. How are road sloped along the side of a mountain? What will have to drain down the mountain, but is it safe this way? Are roads sometimes sloped into the mountain with water draining underneath via pipes and drainage channels? Yes
24. What is an equal tangent curve?
25. What are two types of vertical curves? Draw a crest vertical curve.
26. How are PVI, PVC, PVT described by stationing?
27. What is recommended lane width. Explain the advantages/disadvantages of narrow lanes
28. What is design hourly volume based on?
29. Why are foreslopes and backslopes necessary.
30. Does climate affect design speed? Yes, design speed in cold weather, snow and ice, probably lower than in summer.
Last modified on 25 August 2009, at 17:10