The pier was built in 1956 and is supported on 58 wooden piles. But what did the pier look like in 2021?

We, Willy Stäubli AG Ing. were commissioned by DLZ Liegenschaften to prepare an assessment of the condition and continued use of the pier in connection with the construction of the relief tunnel. A diving team was deployed to adequately assess the pile foundation.

The pier was built in 1956 and is supported on 58 wooden piles. The pile-driving logs are no longer available. Large settlements are not visible, so the load-bearing capacity is guaranteed. Over time, the pier was undermined and the pile heads were exposed. As soon as the fir piles are no longer in the lake bed, they are worn down by natural influences such as wave action or the current. We randomly removed algae and shells from two wooden piles using HD cleaner to determine the original mass. The structural concrete was also visible again after this cleaning.

The bottom line is:

The concrete can be cleaned with the high-pressure nozzle, but the material is crumbling away in places. No major cracks were detected below the water level. In places there are exposed reinforcements, which are also heavily corroded.

The situation must be monitored closely, as the algae growth under water makes it difficult to detect any cracks.

We estimate the remaining useful life at 10-15 years