Movable bridges are always a wonder. There are numerous hydraulic bridge structures in the world that ease transportation facilities. The hydraulic system will help to lift, lower, or fold the bridge safely to avail transportation through various channels. The footbridge Kieler Hörn in the city of Kiel in the German state of Schleswig-Holstein is one of the popular pedestrian’s bridge that crosses Kiel Fjord. This is the path that connecting the main train station to the inner harbor at the southern end of Kiel Fjord. The three-segment folding bridge Kieler Hörn can allow water transportation when required and under normal functioning, it will be a footbridge that carries pedestrians and cyclists. This footbridge will not only ensure safe and robust operation, but this is also a visual and technical attraction of the locality.
Next, we can consider the history and specifications of the Kieler Hörn movable bridge. This three-segment bascule bridge was designed by Gerkan, Marg, and Partners in 1997. The entire length of the bridge is 105 meters and among this, the length of three folding segments is 25.5 meters. Also, the deck has a width of 5 meters. For opening and closing purposes, this bridge will require approximately 2 minutes. The drive system contains 2 hydraulic motors with 44 kW and constant torque winches. Steel is the material used for the construction of the deck and pylons of this bridge. This is the world's first and only three-segment bascule bridge and it forms the shape of a capital “N” when opened for water transportation.
This hydraulically operated three-segment retractable bridge weighing 54tonnes can be lifted and lowered easily to avail the transportation of small and mid-size boats. An electric motor was previously used for powering the bridge. But, at present, this bridge uses two hydraulic jacks to power the system. Among the three segments, one portal is connected rigidly with the deck, and the remaining portals have hinged joints at their bases.
How is Kieler Hörn operated? The lifting and lowering of this three-segment bascule bridge are handled using an integrated complex cable system that containing various ropes, winches, and rollers. The bridge architecture also needs the ability to withstand the wind load applied. When considering the bridge structure, it contains cable drums connected to single-speed winches that rotate continuously for folding the deck. The operation of winches is driven by two 44kW hydraulic motors. The hydraulic system will pressurize the fluid to the required rate and makes the winches operate at constant torque. The generated hydraulic power is converted to mechanical output with the attached hydraulic motor.