Annual average daily traffic

The traffic intensity is a parameter in transport planning and gives the vehicle throughput per unit time again. It thus serves the assessment of quality, efficiency and safety of traffic flow and provides the basis for a traffic engineering dimensioning in road design-and rather Together with other parameters such as traffic density or speed, can create a fundamental diagram of traffic flow.

Definition

When traffic intensity is defined as the number of traffic elements of a traffic stream per unit time at a cross section (local observation). One speaks in this case of the strength of a traffic stream.

Rated traffic intensity

In the definition above, the unit of time can in principle be chosen arbitrarily. Used but very short time units one (eg minutes ), then a very short, currently prevailing traffic condition is considered. Between the studied time units occur on so pronounced fluctuations. For testing purposes the consideration of these fluctuations and peak values ​​does not make sense. It is therefore in practice gone over for the traffic engineering design ( for example, a road cross-section ) is a unit of time of one hour ( authoritative hourly traffic volume, short- MSV ), a day ( average daily traffic volume, short DTV) or weekdays ( Mon-Fri, average daily traffic on weekdays, just to use DTVw ). This design traffic volumes are determined either by an automatic elevation ( continuous counting stations with annual evaluation) or with the help of short-term counts.

The following rules of thumb can be used to determine the design traffic volume qB. Account shall be taken either values ​​of the average daily traffic volume (DTV in vehicles/24h ) or short-term counts from 15.00 bis 19.00 clock with a.

Where a more detailed derivation needed, the corresponding design traffic volumes for out - and urban roads are given in the guidelines.