41.3.1. Two phase signals

Try these first

1. 1.

   Define what a phase is in traffic signal design.

   Hint

   Think about what happens during a traffic signal change.

2. 2.

   What is the significance of grouping non-conflicting flows?

   Hint

   Consider the relationship between efficiency and safety.

3. 3.

   What does a phase in a traffic signal refer to?

   • Only the green light
   • The complete cycle of lights
   • The green interval and change intervals

   Hint

   Consider what happens when lights change.

4. 4.

   Two-phase signals are most effective when:

   • True
   • False

   Hint

   Think about the flow of cars.

5. 5.

   Design a two-phase signal for an intersection where there are two through lanes, one left-turn lane and one right-turn lane. Discuss how you would group the flows and any potential conflicts.

   Hint

   Consider how traffic flows intersect and potential accidents.

6. 6.

   Evaluate a scenario where high left-turn traffic is present at a two-phase signal. What adjustments would you recommend?

   Hint

   Think about how turning movements affect all vehicles at the intersection.