Large new bridges across the fjords are on their way in Norway. Before building the bridges, it is important to know the strength and the structure of the wind where the bridges are to be situated. DTU Wind Energy has been hired as a consultant on the wind measurements at the large constructions.
The Norwegian project “Ferjefri E39” is about discontinuing the ferries across the fjords at a distance of 1100 kilometers along the Norwegian coast and replacing them with tunnels and bridges. The fjords are many at the Norwegian coast; thus many building activities are on their way. If the fjord is too deep or the distance across the fjord is too long a tunnel is not an option and a bridge is to be built instead. In order to find the optimal places for the bridges it is important to know exactly how the wind is blowing the places that were chosen. Consequently the Norwegians have bought the software DTU Long Range Wind Scanner Software from DTU Wind Energy which the company Kjeller Vindteknikk is using for the measurements. The WindScannner can map the areas, where the wind is blowing, in 3D, e.g. areas surrounding wind farms, bridges and mountains.
The role of DTU
DTU Wind Energy is counselling on the use of the software. The researchers and development engineers of the department are teaching the Norwegians how to programme the software and assisting starting up the measurements. Senior researcher at DTU Wind Energy Michael Courtney tells about the task: ”We are delivering general metrological counselling and contribute in cooperation with other experts to figure out how to measure the wind where the bridges are going to be placed.” The wind close to the mountain side is complicated but it can be understood really well from graphic presentations of measurements of WindScanners – e.g. at pictures of the patterns of the wind at the fjord, Michael Courtney explains.
Knowledge of the wind is useful too, when estimating the amount of materials for the bridge. Knowing the speed of the wind is of great importance when calculating the amount of steel that is going to be used for the bridge.
At Halsafjorden close to Trondheim the measurement equipment, i.e. the lidars, are now installed for the measurements of the wind. The lidars are used for the measurements because the water in the fjord is too deep for placing measuring masts. With the measuring equipment in position the measurements for the giant bridge are soon to begin.