LES TRAINS ET LE CHEMIN DE FER APRÈS LA GUERRE, LA RECONSTRUCTION DU PONT TOURNANT DE CARONTE

Supported by eleven stone piles supporting a series of metal beams, the railway viaduct that crosses the Caronte pass stretches for a little less than a kilometer in length. It is one of the many structures on the Miramas-L'Estaque railway line. The Paris-Lyon-Mediterranean Railway Company (PLM) began construction in 1906. The site was completed in 1915, but the official opening, delayed by the First World War, took place in 1922. Located between 6 and 24 m underwater, the foundations consist of masonry blocks anchored more or less deeply in the ground. Their construction requires the use of submerged caissons, weighted with water and supplied with air by pumps. The working conditions are particularly difficult. The bridge piers correspond to a generic model: a rectangular-based truncated pyramid adorned with stones from the Ruoms quarries in Ardèche. The metal frame of the bridge resting on the piers is made of extra-mild steel. The factory-prefabricated beams arrive from Marseille by rail. Assembled on a platform at the edge of the station, they are then placed on their piers by launching from overhead cranes. In 1944, as the occupying troops sought to cover their retreat to the Rhône Valley by delaying the advance of the landing troops, the Germans sabotaged the Caronte railway viaduct. It would not be put back into service, with a temporary span, until 18 months later. The railway viaduct was temporarily replaced by a sort of transporter bridge until its reconstruction in 1954. In this documentary, follow this reconstruction step by step, filmed by André Perié for the Central Cinematographic Section of the SNCF, we learn, among other things, that the first bridge pivoted on "an 83 cm bronze lens" and that the reconstruction was carried out in several phases, first with a temporary Krupp-type lifting span bridge (a war prize) before the swing bridge was completely rebuilt in 1954. http://www.michelchevalet.com/