Inputs
Add critical lane group flow ratios y = q/s for each phase. Tool computes Y = Σy and optimum cycle.
| Phase | q (vph) | s (vph) | y = q/s |
|---|
Method — Webster (1958)
- C₀ = (1.5·L + 5)/(1 − Y).
- Effective green for phase i = (yᵢ/Y)·(C − L).
- If Y ≥ 0.95 the system is over capacity; redesign needed.
Results
Y = Σy—
Optimum cycle C₀—
Recommended cycle—
Effective green Σ—
Phase greens—