Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.
Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.
(OP)
Greetings to all members,
I have pleasure to join the forum of traffic engineers.
A little intro of myself. My name is Rizwan and I am working in UAE in a consultancy as traffic engineer with 3 years experience. We won a project of design of an interchage (currently in concept design stage) and I am working on traffic study of the same. In this regard, i have following questions. I will appreciate the suggestions from all. Thanking all in advance.
Q-1: Any standard process to calculate Design Hour Factor (K) from existing traffic count data?
Q-2:I have a peak hour traffic volume of 12000 veh/lane on a freeway facililty in particular direction.Total lanes are 6. K factor is 0.082 (calculated using traffic volume in both directions)
How can we convert the peak hour traffic volume to daily 24 hour traffic volume? If I use the formula DDHV=ADT*K for ADT calcualtion, the resultant value of ADT looks very high.
I have attached an excel file for K-factors that I calculated from traffic count survey data for AM LT & PM peaks at a certain location on highway.
I have pleasure to join the forum of traffic engineers.
A little intro of myself. My name is Rizwan and I am working in UAE in a consultancy as traffic engineer with 3 years experience. We won a project of design of an interchage (currently in concept design stage) and I am working on traffic study of the same. In this regard, i have following questions. I will appreciate the suggestions from all. Thanking all in advance.
Q-1: Any standard process to calculate Design Hour Factor (K) from existing traffic count data?
Q-2:I have a peak hour traffic volume of 12000 veh/lane on a freeway facililty in particular direction.Total lanes are 6. K factor is 0.082 (calculated using traffic volume in both directions)
How can we convert the peak hour traffic volume to daily 24 hour traffic volume? If I use the formula DDHV=ADT*K for ADT calcualtion, the resultant value of ADT looks very high.
I have attached an excel file for K-factors that I calculated from traffic count survey data for AM LT & PM peaks at a certain location on highway.





RE: Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.
RE: Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.
6 x 2000 = 12,000 Total PHF in 6 lanes
10 x 12,000 = 120,000 AADT
So in terms of order of magnitude I think you're OK.
The two thousand vehicles per lane in the peak hour is a fairly high starting point; in the UK that's approaching the figure for the maximum sustainable hourly throughput according to TA46/97 (and assuming 15% HGVs).
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RE: Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.
Your mileage (kilometerage?) may vary.
Maybe the tyranny of Murphy is the penalty for hubris. - http://xkcd.com/319/
RE: Design Hour Factor (K) Calculation & peak hour traffic conversion ADT.