18.1 - Overview
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Practice Questions
Test your understanding with targeted questions
What is a valley curve?
💡 Hint: Think about what happens when a road goes downwards.
What shape is preferred for valley curves?
💡 Hint: Remember the name has two words; what does it relate to?
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Interactive Quizzes
Quick quizzes to reinforce your learning
What are valley curves primarily used for?
💡 Hint: Think about how roads deal with hills and valleys.
True or False: Valley curves are only necessary during the day.
💡 Hint: Consider what happens after dark.
1 more question available
Challenge Problems
Push your limits with advanced challenges
A new road is to be constructed through a steep valley. If the descending gradient is n = 1 in 25 and the ascending gradient is n = 1 in 30, calculate the required length of the valley curve for a design speed of 80 km/h. Assume c = 0.6 m/sec³ and SSD = 127.3m.
💡 Hint: Break down the problem using comfort and safety criteria as you learned about.
Discuss what factors would lead to the decision to use a longer or shorter valley curve based on gradient changes and nighttime visibility.
💡 Hint: Consider how gradients impact perceived visibility and safety needs.
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Reference links
Supplementary resources to enhance your learning experience.