Hi Arash !

We have estimated the peak hours traffic for Herat city by using camira and film recording for different sections of a corridor ! Then the number of various vehicles been summarized .

If the diurnal distribution is known, this can be derived. Standard conversions exist, but are likely to be very different in different settings/countries.

Let me flip the question around -- many people would much prefer to have the peak flows than attempt to parcel the total daily flows into sub-stages. If you have the two peaks (let's call them A and P for am/morning and pm/afternoon) we know

daily = A + P + factor,  or maybe (A + P ) (times a factor)

representing additive or multiplicative options.

if you knew how much of the day is accounted for by the peak you would be done

for then daily could be derived from something like  (A+P) (1+x)

so, what are probable values of x? you could assume .1, .2, .3, ... and get ranges of the daily total average volume and plot these vs assumed x to get a reasonable (in your experience) data point.

Hi Arash

If you have daily traffic count at the subject location or nearby location that was done in the past, you can derive an equation for the relationship between the peak hours and the daily traffic distribution. Then use this equation to get the daily traffic at any time keeping in mind that this method can be only used in absence of recent data and assuming that there isn't major changes happened since the date of the previous count.

 Dear Arash:

Expanding short counts (less than 24 hours) to ADT can be done using hourly, daily and monthly expansion factors. These factors normally take seasonal changes into account. Search for articles in the area of traffic forecasting and seasonal adjustments. That should help

Dear Arash

for converting a 1 hour counting result to an ADT-value, you need to know the variation patterns of the traffic volume on the road in question. That means, that you have to know the seasonal variations, weekday variations and the hourly variations. The question is of course, where you can get these patterns, if there has not been continuous countings on the road in question. Usually the road administrations and city transportation offices have information of typical variation patterns collected from different types of roads in different areas. Further on, it is also important to choose the 1 hour counting period carefully. Choose a time of day with a representative volume (not too small, but not necessarily the peak hour either). In general the accuracy of the estimation increases with volume, but it is possible, that certain daytime hours between peak times are more stable than the peak volumes. Choose also a normal weekday (no special events or other irregularities in flow). If possile, repeat your count some other day. To get the ADT form one hour traffuc, you first have to count the daily estimate from your one hour value by the knowledge of the share of this hour from the whole day in your reference location. After that, you convert the value to correspond an average weekday based on the weekday variations and finally you convert your average weekday to yearly average. In a nutshel, what you need is a reference location for each of your counting sites and based on the variation patterns of the reference locations, you can estimate the ADTs for your counting points. For example the general text in HCM gives examles of the calculations and variation patterns.

Best regards