41.6. Determination of cycle length

Try these first

1. 1.

   What is cycle length?

   Hint

   Think about how the traffic signal changes from green to yellow to red.

2. 2.

   Define lost time in traffic signal management.

   Hint

   Consider delays when the light changes.

3. 3.

   What is the formula for calculating total lost time?

   • L = N × t
   • L = N + t
   • L = N / t

   Hint

   Remember that N represents phases and t represents time.

4. 4.

   True or False: Effective green time includes lost time.

   • True
   • False

   Hint

   Think of what green time signifies.

5. 5.

   A traffic signal has 5 phases, with each phase experiencing 4 seconds of lost time. If the saturation flow rate is 2400 vph and the critical volume during peak hours is 1800 vph, determine the cycle length.

   Hint

   Apply the values systematically to reach the final answer.

6. 6.

   If a signal has a cycle length of 80 seconds, with startup lost time of 3 seconds per phase, four phases, and a critical volume of 1200 vph, how does this impact the effective green time?

   Hint

   Think about the balance between cycle length and lost time.