Question

A horizontal curve is to be designed in a region with limited space. Which of the following measure(s) can be used to decrease the radius of curvature?

• A. Decrease the design speed.
• B. Increase the superelevation.
• C. Increase the design speed.
• D. Restrict vehicles with higher weight from using the facility.

Hint:

To reduce the radius of curvature for a horizontal curve, either decrease the design speed or increase the superelevation.

Answer 1

The Correct Option is A, B

The radius of curvature for a horizontal curve is influenced by the design speed and superelevation. To reduce the radius of curvature, the following measures can be taken:

Step 1: Decrease the Design Speed.
The radius of curvature is inversely proportional to the square of the design speed, so decreasing the design speed will allow for a smaller radius of curvature.

Step 2: Increase the Superelevation.
Increasing the superelevation (banking of the curve) reduces the need for a larger radius of curvature, as it allows the vehicle to negotiate the curve at a higher speed without sliding outwards.

Step 3: Conclusion.
The correct measures to decrease the radius of curvature are decreasing the design speed and increasing the superelevation.

Final Answer: \[ \boxed{(A) \text{ and } (B)} \]