In this project, Anderten lock was repaired with non-metallic reinforcement.

The chambers were originally built as reinforced concrete walls with an inner brick lining. As a special feature, five levels of economizer basins are arranged one above the other on each side of the chamber walls. The water exchange between the economizer basins and the chamber takes place via cylindrical gates in central shafts. At a height of around 2 m, there was a longitudinal crack with a large crack width on the chamber-side wall of the bypass channel, which ran almost the entire length of the channel. The crack continues into the cross-section with a lesser degree of severity, also on the side of the bypass channel facing away from the chamber wall (on the side of the overflow channel) at a comparable height.

The Federal Waterways and Shipping Administration (WSV) is responsible for the operation and maintenance of the Mittelland Canal / Elbe Lateral Canal. During the last construction inspections in the eastern circular channel of the west chamber, a significant increase in damage to a horizontal crack on the chamber side was detected. On the chamber side in the composite area between the concrete and the masonry extension.

The BAW was commissioned to assess the damage found, to investigate the cause of the damage and to develop possible repair measures. The aim was to prevent the flow of water in the damaged construction joint so that further corrosion of the reinforcement would be avoided or minimized. In addition, the strengthening of the edge zone of the chamber wall and the circulation channel, in particular in the area of the longitudinal cracks (construction joint), was carried out to restore or increase the serviceability.

The substrate preparation and concrete removal in all areas was carried out using a combination of the high-pressure water jet method, manual chiseling and compressed air blasting with solid abrasives.

  • Total duration 10 weeks (including preparation and follow-up)
  • Sprayed concrete work 6 weeks (including substrate construction and reprofiling of the construction joint)
  • Sprayed concrete approx. 16 tons
  • Textile carbon reinforcement 276 m² (of which approx. 20% was for overlappings/trimmings)

 

Images: (c) BAW and ibac, RWTH Aachen University

Key facts

Application Restoration & Repair
Product  solidian ANTICRACK carbon
Year  2023
Location Germany, Hannover
Type
  • Double-chamber lock
  • Dimensions: Total length: 227.5 m / chamber width: 12.0 m

Concrete restoration & repair for a longer service-life of existing buildings

BAW-MITEX:

BAW Bundesanstalt für Wasserbau is a state body and operates hydraulic structures in Germany. The BAW defines rules for the repair of waterway infrastructure (e.g. for locks, inland and maritime waterways) in their fact sheet "BAWMerkblatt" and is actively promoting the topic of carbon reinforcement.

The core competencies of our solidian reinforcements are ideal: no corrosion and the most effective limitation of crack widths, both aspects that bring many advantages when renovating hydraulic structures.

The BAW bulletin (1st edition in 2019) is equivalent to a “guideline”. It regulates renovation measures when there is no pressing water, which is rarely used in practice because pressing water is usually present. solidian ANTICRACK Q85-CCE-21 is currently the only certified grid here. The new BAW bulletin (2nd edition in 2025) will regulate applications with pressing water. This offers a high application potential for significantly more projects. Here, too, solidian ANTICRACK Q85-CCE-21 will again be the only certified grid.