40.5. Capacity

Try these first

1. 1.

   What is the weaving width range listed in the formula?

   Hint

   Think about the design limitations set for rotaries.

2. 2.

   What does the capacity of a rotary refer to?

   Hint

   Consider what affects traffic flow.

3. 3.

   What is the purpose of the empirical formula in rotary capacity?

   • To assess traffic volume
   • To calculate the capacity of weaving sections
   • To design roadways

   Hint

   Focus on the key objective of the formula.

4. 4.

   The proportion of weaving traffic is recommended to be between which ratios?

   • 0.4 and 1
   • 0.1 and 0.5
   • 0.5 and 0.8

   Hint

   Think about the acceptable limits set by traffic studies.

5. 5.

   Given the following conditions at a rotary: Entry width = 9m, Exit width = 7m, Weaving width = 11m, Proportion of weaving traffic = 0.65; calculate the capacity using the empirical formula.

   Hint

   Use the empirical formula, paying close attention to units.

6. 6.

   How would reducing the weaving width to 5m affect the overall capacity of a rotary?

   Hint

   Consider how reduced space affects vehicle maneuvers.