Questions and Corrections
Maria Alice Jacques
Page 14-11: The Manual says: “Also, when the multilane highway segment is undivided or has a TWLTL, no left-side lateral clearance restriction is assumed, and a value of 6 ft is applied because there is a separate adjustment for the type of median that accounts for the impact of an undivided highway on FFS”. However, in Exhibit 14-10, fM for TWLTL is equal do zero (there is no adjustment for this median type).
Page 14-23: The specified typical conditions for rural and urban multilane highways, according to Exhibit 14-18 and Exhibit 14-19 (see the bottom of the exhibits), should be: Percent HV = 12% (rural), 8% (urban); PHF = 0.88 (rural); 0.93 (urban).
In addition, the results presented in Exhibit 14-18 are compatible to FFS = 50 mi/h and not to FFS = 60 mi/h. In Exhibit 14-19 the results are compatible to FFS = 60 mi/h as indicated in the bottom of the exhibit.
Page 14-25: Please check the results presented in Exhibit 14-19 for K-Factor equal to 0.12. It seems that these results are for K=0.11.
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