Elevated crossing over German National Roadway no. 42

• Published in: Informes de la Construcción
• Main Author: Polensky & Zöllner, Constructora
• Format: Article in Journal/Newspaper
• Language: Spanish
• Published: Consejo Superior de Investigaciones Científicas 1965
• Subjects: Elevado; Curva; Andenes
• Online Access: https://informesdelaconstruccion.revistas.csic.es/index.php/informesdelaconstruccion/article/view/4359; https://doi.org/10.3989/ic.1965.v18.i172.4359

National Road no. 42 runs along one of the shores of the river Rhine in the neighbourhood of Rhöndorf. It is crossed by a secondary road by means of an elevated crossing, which can carry light vehicles and pedestrians. The crossing is 136.5 m in length, and consists of five spans, whose lengths are 23.6, 32.1, 32.1, 28.7 and 20 m. The width of the deck is 5.5 m, of which 4 m are taken up with the road pavement, and the rest with two lateral footpaths. The structure is a boxgirder. It is a prestressed, continuous beam, which runs along a curve. Access to the bridge is along ramps built on soil embankments. Owing to the curved planform of the crossing, the torsion forces on the structure are relatively important, but the special distributions of the prestressing cables has made it possible to counteract this loading effect in a satisfactory manner. The hollow reinforced concrete supports are trapezoidal in cross-section, and have hinges at the top and 1 bottom. Thus they act as pendules. The tubes containing the prestressing cables are injected with cement after the cables have been stretched, in accordance with the technique of the contractors, Messrs. Polensky & Zöllner; a firm of worldwide reputation. La carretera nacional número 42 se extiende a lo largo de una de las márgenes del río Rin, en las inmediaciones de Rhöndorf; el cruce con un camino secundario se salva mediante un paso superior, para vehículos ligeros y peatones, que tiene 136,5 m de longitud total, subdividida en cinco tramos de 23,6; 32,1; 32,1; 28,7, y 20 m de luz, respectivamente. La anchura del tablero es de 5,5 m, de los que 4 m corresponden a la calzada y 1,50 a dos andenes laterales e iguales. La estructura resistente es una viga-cajón, continua, pretensada, cuyo eje tiene forma de U muy aplanada. Los accesos al paso están constituidos por dos rampas apoyadas sobre terraplenes. A causa del trazado en curva, los efectos de torsión tienen relativa importancia, pero la disposición adecuada de las armaduras del pretensado ha permitido ...