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The design speed for a two-lane road is 80 kmph. When a design vehicle with a wheel base of 6.6 m is negotiating a horizontal curve on that road, the off-tracking is measured as 0.096 m.The required widening of carriageway of the two-lane road on the curve is approximately
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- 0.55 m
- 0.65 m
- 0.75 m
- 0.85 m
Correct Option: C
| Off tracking means mechanical widening, i.e. | ||
| 2R |
| 0.096 = | = | ||
| 2R | 2R |
∴ R = 226.87 m
| Psychological widening = | = | = 0.56 m | ||
| 9.5√R | 9.5√226.87 |
Total widening = 0.56 + 2 × 0.096 = 0.75 m
