15.4.1. Mechanical widening

Try these first

1. 1.

   What is mechanical widening?

   Hint

   Think about the curvature of a road and vehicle paths.

2. 2.

   Why do vehicles off-track?

   Hint

   Consider the geometry of a turning vehicle.

3. 3.

   What is mechanical widening primarily concerned with?

   • Clearance for emergency vehicles
   • The vehicle off-tracking phenomenon
   • Improving aesthetic appeal

   Hint

   Recall what happens when vehicles navigate a curve.

4. 4.

   True or False: Off-tracking only affects large trucks.

   • True
   • False

   Hint

   Consider the dynamics of different vehicle types.

5. 5.

   Given a highway curve with R = 300m for a vehicle with a wheelbase of 15m and two lanes, calculate the extra width needed.

   Hint

   Consider the formula with the lane count in mind.

6. 6.

   Explain how mixed traffic conditions influence mechanical widening requirements on a curve.

   Hint

   Think about how different vehicles curve differently.