Clear run to Versoud

Construction of a road bridge using Mammut 350 and SecuritBasic

Data & Facts

  • Project
    • Versoud road bridge, France
  • Principal
    • Communauté de commune du Gresivaudan
  • Contractor
    • Baudin Chateauneuf
  • MEVA systems
    • Mammut 350 wall formwork
    • SecuritBasic safety system
  • Engineering and support
    • MEVA Systèmes de Coffrage SNC, France

Construction of a road bridge using Mammut 350 and SecuritBasic

During bridge construction there is generally one common prerequisite: the flow of traffic should not be impaired. The work thus needs to progress quickly and smoothly – as was the case during the construction of the abutments of a bridge over railway tracks in France.

Traffic in Grenoble Metropolitan Region is heavy. In order to improve mobility and boost economic development to the north of the city, a 1.7-kilometre-long transversal road between Le Versoud and Villard-Bonnot was commissioned. This new road crosses a railway line. The construction company Baudin Chateauneuf commissioned MEVA to provide the formwork systems for the bridge abutments. 550 m² of Mammut 350 wall formwork panels and the SecuritBasic safety system were used.

Formwork next to the railway tracks
In order to disrupt the rail traffic to the smallest extent possible, Baudin had to pour every bridge pier in a single cycle in one day, which involved pouring 350 m³ of fresh concrete in ten hours. At the same time the cantilevers of the piers had to be integrated. A 79 cm cantilever had to be poured at a height of approximately 10 metres. To avoid large wood fillers, MEVA suggested using STB corner frames, thus allowing formwork to be created that corresponded to the pier geometry. The formwork was located directly next to the railway line, which meant that the experts from Baudin also had to take into account the airflow from the passing trains when calculating the stability.

On the construction site the Mammut 350 wall formwork with forming surfaces up to 8.75 m² per panel (350 x 250 cm) was able to make full use of its strengths. The system, which has a capacity of up to 100 kN/m², can easily cope with the fresh-concrete pour speed corresponding to a pressure loading of 70 kN/m². The modular SecuritBasic safety system with non-slip aluminium checkered sheeting and access ladders ensured safety when working at heights. The complete unit comprising a safety system and wall formwork panels was assembled safely and easily on the ground and moved into position by crane.

Trouble-free project
The bridge was completed In the summer of 2019 after trouble-free execution of the forming work. At the end of 2020 the last construction phase of this important transversal road will be opened to traffic. The improved transport link will be finished and nothing will hinder the expansion of two newly built intermunicipal industrial estates.

François Rigaldies, senior civil engineer at Baudin, is satisfied: “The MEVA team was able to offer us a solution without additional decking or heavy shoring for the cantilevering of the header. It was this argument that guided our choice of formwork system. Thus, the pouring of each pier was carried out in a single cycle, i.e. 350 m³ of concrete were poured in 10 hours.”