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Pages 168-187

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From page 168...
... P A R T 3 High-Level Analyses The sections in Part 3 of the Guide describe high-level analysis methods that work best when evaluating highway systems at an areawide level. These methods enable the analyst to cover large geographic areas with hundreds of miles of highways very efficiently.
From page 169...
... 173 Q Corridor Quick Estimation Screenline Analysis 1.
From page 170...
... 174 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual the corridor where high vehicle volumes suggest that the intersections should be checked for potential LOS problems. Exhibit 121 illustrates a set of corridor screenline checks for the freeway and arterial corridor shown in Exhibit 120.
From page 171...
... Q. Corridor Quick Estimation Screenline Analysis 175 AADT per Lane Mixed Flow v/c Screening Multimodal LOS Screening Freeway Arterial Screenline Freeway Arterial Freeway Arterial Corridor Auto Auto Transit Bike Ped 1 16,500 3,300 83% 24% 59% LOS D LOS C LOS F LOS D LOS E 2 16,100 4,800 81% 36% 63% LOS D LOS C LOS F LOS D LOS E 3 20,900 7,700 105% 57% 86% LOS F LOS D LOS D LOS E LOS D 4 16,600 7,600 83% 56% 72% LOS D LOS D LOS D LOS E LOS D 5 17,300 3,500 87% 26% 62% LOS D LOS C LOS F LOS D LOS E 6 13,900 N/A 70% N/A 70% LOS C N/A N/A N/A N/A Notes: N/A = not applicable (arterial not present)
From page 172...
... 176 R Areas and Systems 1.
From page 173...
... R. Areas and Systems 177 4.
From page 174...
... 178 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual Multilane Highway Segments (see HCM Equation 12­1)
From page 175...
... R. Areas and Systems 179 creation of local look­up tables so that they accurately reflect the free­flow speeds present in the locality.
From page 176...
... 180 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual PHF = peak hour factor, and CAF = capacity adjustment factor (locally developed and applied to match field measure­ ments of capacity, when available) , default is 1.00.
From page 177...
... R. Areas and Systems 181 Rural Two-Lane Highways and Roads Equation 198 (adapted from HCM Equation 15­3)
From page 178...
... 182 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual fbb = adjustment factor for blocking effect of local buses that stop within intersection area (decimal) , fa = adjustment factor for area type (decimal)
From page 179...
... R. Areas and Systems 183 5.
From page 180...
... 184 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual Demand Models That Compute Mode Delay. If mode delay is used by the demand model, the following equation is used to compute average link speed, including mode delay.
From page 181...
... R. Areas and Systems 185 The BPR curve (Equation 201)
From page 182...
... 186 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual applicable to only those individual facility types and begin to lose their meaning (masking out problem spots within the facility) when applied to facilities more than 10 miles in length.
From page 183...
... R. Areas and Systems 187 Density Density can be computed for each roadway link by dividing the demand model's predicted directional volume in vehicles per hour per through lane by the demand model's predicted aver­ age link speed in miles per hour.
From page 184...
... 188 S Roadway System Monitoring 1.
From page 185...
... S. Roadway System Monitoring 189 the speed limit.
From page 186...
... 190 Planning and Preliminary Engineering Applications Guide to the Highway Capacity Manual • If the TTI falls between 1.05 and 1.40, then it is uncertain whether the link is over capacity or not. Further information on the facility's speed at capacity is needed to make a determination.
From page 187...
... S. Roadway System Monitoring 191 6.

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