Nordic Road and Transport Research 2-2004

Page 21

Annotated reports from Technical Research Centre of Finland (VTT), Building and Transport

The Potential for Traffic Enforcement in Finland About 400 persons are killed in traffic accidents in Finland annually. A traffic safety goal of not more than 250 fatalities has been set for 2010. Among other things, achievement of this goal also requires intensification of traffic enforcement. The way the volume of traffic enforcement, selectivity, methods and technology should be developed during this decade was estimated in a research project at VTT. According to the results of the study, the most effective way to reduce traffic fatalities in Finland by enforcement is to develop and intensify the use of speed cameras. There is a potential for decreasing annual road traffic fatalities by 35–65 (9–16 %). Intensifying enforcement of the use of safety belts and enforcement of drunken driving regulations could each drop the incidence by over 10 (3%) fatalities annually. It has to be noticed that drunken driving regulations are

already intensively enforced in Finland. The number of annual breath tests is equal to about 40 per cent of the driver population. There is more potential for intensifying the enforcement of seat belt use. It should be enforced especially in passenger cars. The development of the methods and technology of traffic enforcement was also examined in the project. The use of machine vision and wireless data transmission is becoming more widespread among technical surveillance equipment. Manufacturers provide a solution for practically all conventional enforcement needs such as enforcement of red light violations, speed enforcement, turning violations, use of bus lanes and monitoring of stolen vehicles by means of automatic license plate identification. However, we noticed that the use of open systems that would allow several providers access to the speed/surveillance camera data, would definitely lower the

costs of surveillance and thus allow a much higher number of surveillance posts to be used. The recording and the notification of violations should be automated as far as possible. It is advisable to use image pattern recognition in speed enforcement. The computer shoud be able to transsmit the recorded speed violation data autmatically to the office system.

Title: Assessment of the potential for enhancement police enforcement Authors: Rita Rathmayer, Veli.Pekka Kallberg, Katri Koskinen, Tapani Mäkinen, Jouko Viitanen Series: Publications 49/2004 Language: Finnish with English abstract

Freezing Used to Support a Railway Tunnel on Bothnia Line, Sweden The railway tunnel on the Swedish Bothnia Line, on the western shore of the Gulf of Bothnia, was the largest artificially frozen structure in the Nordic countries. The tunnel that was completed in 2003 was temporarily strengthened by freezing. Although a challenging and unconventional construction method, freezing turned out to be the best approach for this particular site from a technical and economical point of view. The preliminary design for bidding was carried out by Golder Associates Ltd on the order of Banverket (Swedish National Railway Administration). Construction planning for the freezing of the Stranneberg tunnel, located five kilometres from Örnsköldsvik towards Umea, was started in November 2001. Freezing took place in the summer of 2002, and tunnel blasting in the autumn of the same year. The tunnel (100 metres long, 10 metres high and 10 metres wide) required more than 5,000 cubic metres of soft soil and weak rock mass to be frozen. Freezing work on the tunnel line was star-

ted in early 2002 with the drilling of freezing holes, and the tunnel broke through the frozen stretch in December 2002. Lemcon Ltd carried overall responsibility for the tunnelling, and VTT was responsible for ground freezing design. The final lining of the tunnel was completed in the spring of 2003, after which the soil was allowed to melt. In the planning phase, the progress of freezing was evaluated, stability and displacement analyses were made, measurements for monitoring tunnel construction were designed, the locations of the pipelines for freezing were planned, and monitoring results were checked. Design calculations were carried out using software Temp/W for thermal and software PLAXIS for geotechnical analysis. The strength and deformation characteristics of frozen soils, besides preliminary testing by the Technical University of Lulea, were also determined. Laboratory tests for the design were carried out in the frost laboratory at VTT. The railway tunnel was constructed at


a depth of 20 metres in the soft ground of organic clay at Stranneberg. Open excavation was not accepted for the tunnel construction, because the deposition of excavated soil might have caused environmental problems. Owing to the large dimensions of the cross section, strengthening the tunnel soil by freezing was considered to be the technically best and safest approach.

LEMCON Ltd Construction Manager Jouko Viitala Phone: +358 9 1599 645, +358 40 538 1768 E-mail: VTT Building and Transport Senior Research Scientist, Dr. Seppo Saarelainen Phone: +358 9 456 4895, +358 40 060 5492 E-mail: