Part C of problem #2 asks for the heavy vehicle adjustment factor (fHV) for going uphill. The grade is 3% for a distance of 2 miles. The truck percentage is 5% trucks and 15% busses, so Pt=20%. What I am trying to figure out is: why would I use the passenger car equivalent for trucks, Et, in Exhibit 20-9 of the HCM (as they did in the solution) and not the Et in Exhibit 20-15? 20-9 gives you Et values for level of rolling terrain and 20-15 gives you values for specific grade ranges for specific distances. Can anyone explain why they solved the problem this way? I guess that I'm still trying to figure out how to use the HCM effectively and any explaniation would help.
Thanks,
Greg
Thanks,
Greg
