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Sub-problem 3a - Page 5 of 13

ID# C403A05

Sub-problem 3a: Weaving Analysis

The results of the calculations are show in Exhibit 4-47. The calculations suggest that both of these weaving sections have adequate levels of service in the AM and PM peaks.

Exhibit 4-47. Weave Analysis Results A & B
Weaving Segment Peak Period Ww Wnw Sw
mph		 Snw
mph		 S
 mph		 Density pcpmpl LOS Type of Operation
A AM 1.11 0.18 41.07 61.59 49.03 16.63 B Constrained
A PM 0.66 0.09 48.06 65.38 54.91 8.53 A Constrained
B AM 0.71 0.09 47.25 65.25 55.95 10.02 B Constrained
B PM 0.92 0.14 43.69 63.38 52.07 13.48 B Constrained

Before concluding that these facilities are operating acceptably, we should note that the weaving sections are longer than the distances that the HCM 2000 methodologies were designed to address. The HCM 2000 says that if the weaving section is longer than 2,500 feet, it should be analyzed as a combination of an on-ramp and an off- ramp, which we did in Sub-problem 2b. For this problem, however, we analyze them if they were only 2,500 feet long, so we’re not outside the range for which the HCM is intended. That produces the results shown in Exhibit 4-47.

Notice that the weaving and non-weaving intensity factors, Ww and Wnw are higher when the volumes are higher. That means they’re higher in the AM peak for Location A and in the PM peak for Location B. This increases the densities and produces a lower level of service.

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