17.5. Problems

Try these first

1. 1.

   Define a summit curve.

   Hint

   Focus on the meeting of gradients.

2. 2.

   What does SSD stand for in road design?

   Hint

   Think about the distance needed to stop safely.

3. 3.

   What is the primary purpose of a summit curve in road design?

   • To enhance visibility
   • To lower construction costs
   • To increase vehicle speed

   Hint

   Think about what helps drivers in difficult situations.

4. 4.

   True or False: SSD is not necessary in road design.

   • True
   • False

   Hint

   Consider the safety aspects of road design.

5. 5.

   Design a summit curve where n = +6.0% and n = -2.0% with a specified speed of 50 km/h and SSD that must be at least 100m.

   Hint

   Use your knowledge of gradients and stopping distances.

6. 6.

   If site constraints limit a summit curve length to 300m, analyze how it affects safety with an increasing gradient of +8.0% and a speed of 65 km/h.

   Hint

   Consider the effects of shorter designs on safety.