Unit 4

Question 1

What are the goals of geometric design (5)

Answer 1

1. Maximise comfort
2. Ensure safety and reduce accidents
3. Ensure high traffic flow with minimum delay
4. Economy of facilities
5. Minimize the environmental impacts

Question 2

Name and describe the three aspects of the design process

Answer 2

1. Location design - the micro-level routing of a planned highway connecting two points
2. Cross-sectional design - consists of things such as curbs and gutters, lane and shoulder widths
3. Alignment
   • Vertical alignment: is represented in a profile view - along it’s length

• Horizontal alignment: consists of horizontal tangents, circular curves and possibly transition curves.

Question 3

Name and describe the 3 types of road classification

Answer 3

1. Functional classification - grouping roads into classes according to the character of service they are intended to provide.
2. Administrative classification - classification according to their local authorities (national, provincial, rural and municipal)
3. Design classification