3.2.8 Validation
Validate existing volumes by checking against field observations, historical traffic counts, traffic volumes from adjacent projects, adjacent land use, and the capacities defined in the HCM. and show the capacities of basic freeway segments, multilane highway segments, and ramps based on the HCM 7th Edition. If there are discrepancies between data points, validate with additional data sources.
Free Flow Speed (mi/h) | Capacity (pc/h/In) | |
---|---|---|
Basic Freeway Segment | Multi-Lane Highway Segment | |
75 | 2,400 | N/A |
70 | 2,400 | 2,300 |
65 | 2,350 | 2,300 |
60 | 2,300 | 2,200 |
55 | 2,250 | 2,100 |
50 | N/A | 2,000 |
45 | N/A | 1,900 |
Ramp Free Flow Speed (mi/h) | Capacity (pc/h) | |
---|---|---|
Single-Lane Ramps | Two-Lane Ramps | |
>50 | 2,200 | 4,400 |
>40-50 | 2,100 | 4,200 |
>30-40 | 2,000 | 4,000 |
>=20-30 | 1,900 | 3,800 |
<20 | 1,800 | 3,600 |