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As no internationally agreed-upon method for determining safe speed values currently exists, collecting vast amounts of information on conventional ship behaviour could be used to train autonomous ship intelligence in determining safe speeds in different conditions. This requires speed data collected from conventional ships to resemble what can be described as safe speeds. To test this, the Automatic Identification System (AIS) and environmental data – namely visibility, mean wind speed and significant wave height – were collected and merged for two study areas in Norway in the period between 27 March 2014 and 1 January 2021. Regression analyses based on 47,490 unique vessel transits were conducted and supplemented by two graphical methods for revealing relationships between variables. Contrary to the contemporary understanding of safe speed, reduced visibility did not lead to significantly reduced transit speeds. Wind and waves caused a reduction in speed in the open ocean, but not in coastal waters. Transit speeds were lower in coastal waters than in the open ocean. [ABSTRACT FROM AUTHOR]

Long-span bridges are the pinnacle of human achievement in structural form, linking communities over vast obstacles. It is understood that bridge stocks are ageing, but there is little global oversight. This article presents a publicly accessible global long-span bridge database of 751 long-span bridges, and provides a data analysis to enable the identification of common problems, future needs, and the relationship between the age, design life, and condition status. The database is available online at and further submissions can be added. Some key points from the analysis are: (1) the US, China and Norway comprise more than half of the world's long-span bridges; (2) almost a quarter of the US long-span bridges are beyond the AASHTO 75-year design life; (3) target design lives are not being achieved with only 12% of bridges completing 75 years before major structural rehabilitation; (4) structural health monitoring is mainly implemented for new bridges, in spite of the clear need for older bridges. The global long-span bridge database should contribute to researchers being able to target key problems in the management of these bridges, thereby contributing to the extension of their operational lives. [ABSTRACT FROM AUTHOR]

The reconstructed route E39 along the west coast of Norway will provide efficient local and regional transportation for people and goods. Efficient transportation implies safety measures exist, e.g., driving speed limits for adverse weather condition. This is especially important for structures in open areas, such as long-span bridges. This paper investigates the path tracking ability and lateral stability of two vehicle types – a tractor-semitrailer (TS) and a sport utility vehicle (SUV) – on the Bjørnafjorden floating bridge considering a 1-year storm condition. At a speed of 108 km/h, the TS experiences a roll-over risk, and at a speed of 90 km/h, it frequently leaves the traffic lane. At the highest speed, the SUV wheels do not lose contact with the bridge deck, but the vehicle does leave the traffic lane. This implies that a TS driver requires more vehicle handling effort over the floating bridge than an SUV driver. Results suggest that a TS can safely enter the bridge at a low speed (36 km/h) and then accelerate to 72 km/h after travelling 2 km. An SUV entering at a speed of 90 km/h and accelerating to 108 km/h after travelling 0.5 km was found to be safe. • The crosswind load influences vehicle path deviation the most. Floating bridge motions do not have a substantial influence on the vehicle's path tracking ability. • The vehicle lateral displacement from the path increases with increasing vehicle speed. • The TS driver would require more effort for vehicle handling over the floating bridge compared to the SUV driver. • The roll-over risk is indicated for the semitrailer at speeds greater than 95 km/h. No roll-over risk is noticeable for SUV. [ABSTRACT FROM AUTHOR]

Efficient transportation is an important factor for regional socio-economic growth. Excitations from wind loads and road motions can influence vehicle-driver behaviour in a way that may impair transportation. This is especially true in open areas such as long-span bridges. This paper investigates the influence of wind loads and floating bridge motions on bus lateral stability for the straight concept solution across Bjørnafjorden in Norway. For this investigation, an 8-degree-of-freedom model of a two-axle coach is used. The defined driver model is based on the pure pursuit path tracking method. The vehicle deviation from the path is found to increase with increasing bus speed. This deviation is significant after the vehicle enters the bridge (e.g., over 0.5 ​m for a speed of 90 ​km/h). At 108 ​km/h, the windward rear wheel loses contact, indicating the potential risk of vehicle roll-over. The mean and root-mean-square values of the handwheel steering angle increase with increasing speed, which might cause difficulty for the driver to control the vehicle. Simulation results suggest that the bus can suitably enter the bridge at a lower speed (e.g., 72 ​km/h) with the possibility of increasing the speed (up to 90 ​km/h) after approximately 2 ​km of travelled distance. • Floating bridge vertical displacements with low angular spatial frequencies prevailing. • Path deviation increases with increasing bus speed. • Handwheel steering angle signals oscillate around a mean value. The mean value increases with increasing speed. • Winward rear wheel could lose contact with the floating bridge deck at the highest speed. [ABSTRACT FROM AUTHOR]