3C. Cross-section elements

Question 1

Which book and chapter can cross-section elements be found?

Answer 1

AASHTO Green book Chapter 4

Question 2

What are the common cross section areas to consider

Answer 2

Border Area - the area between the roadway and ROW line
Traveled way - the part of the road that can be driven on
Roadway - The travelled way and the shoulder

Question 3

What is the accepted rate of cross slopes

Answer 3

AASHTO Chapter 4

1.5% to 2% for paved
2% to 6% for unpaved

Question 4

What is the standard lane size

Answer 4

AAHSTO chapter 4

9’ to 12’ with 12’ being the most common

AASHTO Chapters 5-8 will have more detailed information on lane widths depending on the roadway type.

Question 5

What are acceptable shoulder widths

Answer 5

10’ is the normal shoulder width
2’ minimum