Geometric Design MCQ with answer and solution

Concept

IRC gives 3.75 m carriageway width for a single-lane road with raised kerbs.

Step-by-step solution

1. Recall IRC standard widths for carriageways. 2. For urban roads, IRC gives 3.5 m for a single lane without kerbs. 3. With raised kerbs, the width is increased to 3.75 m. 4. So the answer is 3.75 m, which is option (A).

Explanation

IRC recommends 3.75 m carriageway width for a single-lane road with raised kerbs. The extra width gives side clearance, because vehicles keep away from the raised kerb. The other options are too narrow for a single lane.

Why the other options are wrong

B: 2 m is too narrow for even one vehicle with clearance. C: 3 m is not the IRC value for a single lane with raised kerbs. D: 2.5 m is close to vehicle width only and has no clearance.

Shortcut

Single lane with raised kerbs means 3.75 m.

Common mistake

Mixing the 3.5 m value (urban single lane without kerbs) with the 3.75 m value (with raised kerbs).