Cykelvägars friktion: mätningar i fält i jämförelse med cykeldäcks friktion på olika underlag i VTI:s däckprovningsanläggning


Skidding is a common cause for cyclists getting seriously injured in traffic. Neither requirements nor prescribed friction measurement methods for cycleways have been based on the performance of bicycles. There is therefore a need for increased knowledge regarding the friction characteristics of bicycle tyres and the traction between a bicycle tyre and the road surface under different conditions. In this project we have compiled measurements with VTI's portable friction tester, PFT, on cycleways with a variety of road conditions. To relate the PFT friction values to the friction of bicycle tyres, we have also made comparative measurements with bicycle tyres in VTI's stationary tyre testing facility. These show a very good match between the PFT friction values and the maximum lateral friction available for a bicycle tyre. This means that the PFT friction values recorded on cycleways can also be said to represent the friction that a bicycle tyre would perform on the same surface. Our friction measurements on cycleways show that the skid resistance is affected by the road condition, the road surface material, as well as road markings and manhole-covers. Ice and snow cause a significantly lower friction level than at bare conditions. Differences in road conditions mean that different types of cycling infrastructure and different winter maintenance methods result in different friction levels. This means that there may be large variations in friction along one and the same cycle route. The surprise effect and thus the accident risk can then be great. Not only snow, ice and grit, but also leaves, clay and other dirt on the surface might lead to a reduced skid resistance. For the safety of cyclists, it is important to inform about where a slippery condition can occur and to adjust anti-icing actions, road design and construction according to that knowledge.



Society for Benefit-Cost Analysis: European Conference 2020

VTI and Centre for Transport Studies (CTS) at Royal Institute of Technology (KTH) organise Society for Benefit-Cost Analysis: European Conference 2020. 

International Cycling Safety Conference

Swedish Cycling Research Centre, Cykelcentrum, organises together with Lund University the International Cycling Safety Conference, ICSC 2020. The conference is postponed to 10-12  November 2021.



Electric scooters are making their way into the accident statistics

The number of accidents involving electric scooters has increased from a few in 2017 to almost 500 in 2019 (January - October). This was also when electric scooters really made their entrance into Sweden's largest cities.


How can the bus trip be improved for people with ADHD?

People with autism, ADHD and other neuropsychiatric disorders may experience difficulties in using public transport, which limits their opportunities for an active life in terms of school, work and hobbies.


Evolution Road – new electric road tested both inside and out

In the beginning of May, the next-generation electric road was inaugurated in the city of Lund in southern Sweden. Ground based conductive charging technology will be tested on a kilometre long stretch of electric road in the bus lane in Getingevägen. This...


Additional policy instruments are needed to achieve Swedish environmental quality objectives for maritime transport

Achieving the national and international environmental objectives for maritime airborne emissions requires a combination of new and more powerful policy instruments. The policies already in place are not enough. This is one of the conclusions of a research...


Opportunities for a new market in electrified regional flight

Large, electrified aircraft is far off in the future. On the other hand, there may be potential for a new market with smaller regional flights. These are the conclusions of a literature survey made by researchers at VTI.


Need for standards as electric road systems are developed

The need for standardisation is increasing as electric road systems are reaching higher levels of maturity. A large part of the standards for intelligent transport systems (ITS) assessed in a new VTI and SIS study was considered potentially useful for...