Trafikkvolum

Trafikkvolum refers to the amount of traffic on a road segment over a given period. In transport engineering, it is commonly expressed as average daily traffic (ADT) or annual average daily traffic (AADT), representing the mean number of vehicles passing a point per day over a year. Traffic volume can also be reported for specific periods, such as hourly volumes, to capture diurnal patterns. Depending on the analysis, volumes may be presented as vehicle counts or converted to passenger car units (PCU) to account for differences in vehicle size and effect on capacity.

Measurement methods: counts are collected with permanent or temporary counting stations using inductive loops, pneumatic tubes, radar sensors, video or camera-based systems. Data may be supplemented with manual counts or modeled from mobility surveys. In data processing, counts are adjusted for undercounting, calibrated, and sometimes converted to PCU; AADT is typically derived from multiple weeks or months of data, excluding anomalies.

Applications: Trafikkvolum is a key input for road design, capacity analyses, and level of service assessments, as well as traffic forecasting, safety studies, and environmental impact assessments. It helps determine infrastructure needs, identify bottlenecks, and monitor changes over time due to land use changes or policy measures. Data are often produced by national or regional transport authorities and published as road traffic statistics.

Limitations and context: Volume is influenced by time of day, day of week, season, weather, incidents, events, and nearby land use. Counts represent a sample of a larger network and may require extrapolation. Trends in mobility, such as shifts to public transit or active modes, can alter the relationship between traffic volume and road capacity. Advances in sensors and data sharing improve the granularity and accessibility of trafikkvolum data.