Calculate the superelevation for a horizontal curve provided with a radius of 400 m for a design speed of 100 kmph in plain terrain.
- A0.04
- B0.07Correct
- C0.10
- D0.11
Solution
Concept
Superelevation
Formula
e = V²/225R ≤ 0.07
Step-by-step solution
1. e = 100²/(225 × 400) = 0.111. 2. Limit for plain terrain is 0.07, so provide 0.07.
Explanation
The calculated value exceeds the maximum permitted.
Why the other options are wrong
0.11 exceeds the maximum.
Shortcut
Cap at 0.07.
Common mistake
Giving 0.11.
Correct answer: B) 0.07