Les ponts de l'ONIA et d'Empalot - La première section de la rocade sud de Toulouse

Both bridges are built with prestressed concrete. The Onia Bridge, 270 M long, consists of 4 continuous spans; it was constructed above the piles by the cantilever method. It varies in width because of the vicinity of an interchange; this caused a number of design problems, but the main difficulty was the foundations. The Empalot Bridge is less conventional. It is a precast girder bridge with 4 spans and 197 M in length. The original feature of the bridge is that it was made continuous after the girders were erected by means of prestressing cables. The length of the girders (50 M) and their weight (153 t) are such that they make this structure one of the most important precast girder bridges built in France. Details are given of the design and construction methods of the two bridges.