Trafiksäkerhetsmodell för länkar på landsbygd
2005 (Swedish)Report (Other academic)Alternative title
Traffic safety model for links in rural areas (English)
The objective has been to develop a new type of model for links on the state maintained road network. The model must be easy to use, have good predictive ability and have an explanatory capacity. It must also be possible for the model to be constantly revised as knowledge gradually increases. Work has concentrated on fatality rate and SSD rate (number killed, or number severely injured or killed, per a certain traffic mileage). The model must, as far as possible, be general and flexible and must also cover combinations of design and speed limits which are not used today. In recent years, there has been an increasing need for models which differentiate on the basis of new types of road, such as 2+1 roads (with different types of barriers at the centre) and which can also differentiate on the basis of e.g. 10-km stages in speed limits, such as 50, 60, 70, 80, 90, 100 and 110 km/h. It is likely that demand will in the first place increase for models that can predict the number killed on the roads. The proposed model takes multiplicative account of type of road, roadside area, alignment/sight line and actual speed level. Given a certain expected fatality rate (or SSD rate) for a certain type of road with a certain actual speed level, the constituent factors can be altered and a new expected rate can be obtained according to the following schematic arrangement: Fatality rate = constant x Road type change x Roadside area change x Alignment/sight line change x Speed change With the help of previously estimated rates and the effects of measures, as well as "expert assessments", the unique effects of the various road factors have been estimated. The significance of a change in speed is easily obtained using the "power model". Perhaps the most important property of the model is that more attention than before is focused on the great significance of speed for the number killed and severely injured on the roads.
Place, publisher, year, edition, pages
Linköping: VTI., VTI rapport 514 , 2005. , 50 p.
VTI rapport, ISSN 0347-6030
Traffic flow, Accident rate, Risk, Mathematical model, Rural area, Road network, Carriageway, Central reserve, Traffic lane
Research subject Road: Traffic safety and accidents, Road: Geometric design and traffic safety; Road: Traffic safety and accidents, Road: Collation of accident statistics
IdentifiersURN: urn:nbn:se:vti:diva-6380OAI: oai:DiVA.org:vti-6380DiVA: diva2:675257