Modernisation of the intermunicipal wastewater treatment plant for the Chambéry urban area

After modernisation of the biofiltering and operations buildings at the start of 2011, the project is now continuing with sludge treatment and external materials treatment activities. 

Three structures designed for sludge treatment:
- 2 circular digesters with prefabricated cupolas + associated technical rooms.
- Structure for treatment of external materials.
- Sludge treatment structure.

Technical difficulties with the digesters:
- Structures 20 metres in diameter with a sludge height of 14.60 m in the centre of the structure.
- Cupolas pre-fabricated with reduced deflection (hence considerable traction forces in the ring at the top of the circular wall).

Photos: Christine CHAUDAGNE

Wastewater treatment plant

Year
Company of civil engineering
EIFFAGE TP RHONE ALPES
Location
Chambéry (73)
Project owner
REGIE DES EAUX DE CHAMBERY METROPOLE
Project manager
BONNARD & GARDEL
Missions

Working designs

Spécificités techniques

Sludge height 14.60 m

Building for sludge treatment + deodorisation:

  • Plan dimensions 38.00 x 25.00. Building height 13 m excluding sludge silo footprint
  • Foundation by general base slab, thickness 0.40 m
  • Presence of some infrastructure tanks, suspended from the general base slab
  • Presence of a sludge silo supported by thick slab and end beam. Plan dimensions 5.70 m x 4.40 m. Sludge height: 11.35 m
  • Fractioning of structure into two blocks for shrinkage


External products building:

  1. Plan dimensions: 45.00 x 22.00. Height 12.00 m
  2. Foundations by general base slab 0.35 m thick
  3. Presence of numerous buried tanks 
  4. Walls 12 m high without intermediate flooring 
  5. Fractioning of the structure into two blocks for shrinkage.
Type
Civil Engineering
Cost of the work
45 000 000 € HT
40 years of cooperation in the service of construction