- Client: HYDRO Exploitation SA
- Site management / reference person: HYDRO Exploitation SA - Christian In-Albon
- Foreman: Jasin Ajeti
- Foreman: Alessandro Salemi
- Construction period: Sept. to Dec. 2023
- Construction costs: 450'000.-
Technical data:
- 30 m³ concrete demolition
- 1,400 m² concrete removal with high-pressure water jets
- 1,400 m² bonding bridge Mapegrout Primer
- 1,500 bonded dowels
- 280 m' formwork for staging
- 250 m³ leveling concrete NPK C
- 260 m³ basalt concrete for new concrete base
Project description:
The bed of the Bitsch flushing channel has been massively eroded since its construction between 1964 and 1967. During construction, a wear layer of 20 cm was placed on the concrete base. This layer has now completely eroded in several places and the underlying concrete base has been attacked very quickly as a result. Erosion depths of up to 60 cm were observed, particularly in the upper section (sections 000 - 420). For this reason, a new wear layer had to be constructed as a priority on the 000 - 420 m section in 2015. During the last flushing in 2020, further erosion damage occurred from km 420, which was repaired in the fall of 2023.
The following work was carried out:
- Rough cleaning of the deposited sediments in the flushing channel.
- Installation of water detour and pump sumps.
- Increasing the roughness of the old concrete base with ultra-high-pressure water jetting, including removal of the hydraulic material.
- Installation of a leveling concrete layer in areas with deep abrasion so that the new basalt concrete layer is approx. 20 cm thick.
- Installation of bonded dowels around fields of 10 m x 10 m.
- Fine cleaning of the surface of the old concrete or the leveling concrete with water pressure. Removal of water in any local depressions in the channel base before concreting.
- Application of a bonding bridge between the old concrete or leveling concrete and the basalt concrete.
- Concreting work with basalt concrete (concrete cannot be pumped) including compacting with two vibrating needles, stripping the concrete surface with a vibrating beam and relief cuts (shrinkage) with a depth of approx. 50 mm every 10 m in the channel floor.
- Application of a curing agent for post-treatment.
Requirements
- Material management & logistics
- Work partly on open waters
- Short construction time
Special features:
- Use of basalt concrete
