Injection of Expansion Joints and Cracks in Hellberg Tunnel
The roughly 160 meter long road tunnel was built as part of the Kirn ring road in the course of the B41 in the early 1960s. Over 9,000 vehicles use this connection every day. Fundamental repair due to wear was therefore urgently required.
After drilling holes and setting the packers, waterbearing cracks were first closed with the quick-curing, moisture-reactive PU Injection Foam Resin WEBAC®150. The injection was then carried out in order to durably seal the 0.2 – 1.0 mm wide cracks with the PU Injection Foam Resin WEBAC®1405. This injection resin is characterised by its very good edge adhesion and expandability, which ensures long-term tightness even if structural components are exposed to high stress levels.
In the course of the concrete repair work it was not an easy task to restore the sealing function in the area of the expansion joints. Thanks to the excellent material properties such as high expandability and strength it was decided to use Injection Gel WEBAC®240 for this purpose. The gel was injected according to the specifications in the building plan. The injection was carried out by means of a 2-component pump with pressure limit and a measuring unit for automatically recording the flow rates.
Thanks to the WEBAC® products used, the reconstructed tunnel is now just like new, fit for the future and will once again fulfill its function of easing traffic in the town of Kirn in the decades to come.