Question

Select the correct sequence of steps for designing the operation of a signalized intersection.

• A. Signal Phasing \(\rightarrow\) Green Allocation \(\rightarrow\) Cycle Length Selection
• B. Green Allocation \(\rightarrow\) Cycle Length Selection \(\rightarrow\) Signal Phasing
• C. Cycle Length Selection \(\rightarrow\) Signal Phasing \(\rightarrow\) Green Allocation
• D. Signal Phasing \(\rightarrow\) Cycle Length Selection \(\rightarrow\) Green Allocation

Hint:

In signal design: First decide phases, then cycle length, then distribute green times.

Answer 1

The Correct Option is D

Step 1: Signal Phasing.
The first step is to decide the number and order of phases (e.g., two-phase, three-phase, four-phase signals).

Step 2: Cycle Length Selection.
Once phases are fixed, the cycle length (total time for all phases) is determined, often using Webster's method.

Step 3: Green Allocation.
Finally, the total cycle time is distributed among phases (green time per approach), based on traffic volume and saturation flow. \[ \boxed{\text{Correct sequence = Signal Phasing → Cycle Length Selection → Green Allocation}} \]