Consider a rural highway with a projected 20-year AADT of 40,000 vpd. For the type of highway and region in question, it is known that peak-hour traffic currently is approximately 20% of the AADT, and that the peak direction generally carries 65% of the peak-hour traffic. What is the DDHV?
[Solution shown below]
An approximate DDHV could be estimated as DDHV = AADT*K*D. K is the percentage of the AADT that occurs in the peak hour and D is the directional distribution percentage.
Therefore, DDHV = 40,000*0.20*0.65 = 4000 vph