B15 Bridge Over the Mangfall River and Canal

Federal Highway B15 is an important Bavarian north–south connection east of Munich’s metropolitan area. The construction of the western section of the Rosenheim ring road (Westtangente Rosenheim) reduces traffic in the town and increases the residents’ quality of life. The heart of the construction is the 192.50 m Aicherpark Bridge crossing both the Mangfall River and the Mangfall Canal. The flexible cable-stayed bridge was the best design for the difficult subsoil conditions. The subsoil, consisting of basin deposits, is a leftover from the ice age and prone to excessive settlement that had to be taken into account. The superstructure counters this problem by means of pylons clamped into the structure and traditional supports. Intelligent move. The entire construction can be lifted if required. The 50 m foundation elements are not visible yet crucial. Bored piles, drainage columns and displacement piles transfer the loads to the marine clay soil. The extradosed bridge with short pylons and shallow cables blends harmoniously into its environment. The structure does not steal the limelight from the tall trees nor from the buildings of the adjacent Aicherpark. The exterior longitudinal girders form a continuous visual band with the pylons. The cables are not anchored into consoles but into the inside of the girders, which creates a structurally, economically and visually durable construction.