Due to irregularities in the subsoil, the steps on the Wilhelminaberg in Landgraaf have subsided. The Wilhelminaberg forms part of the Park Gravenrode leisure area. The subsidence of several steps was both a nuisance and a hazard to walkers and sports enthusiasts.
The Wilhelminaberg originated as a spoil tip for the Staatsmijn Wilhelmina (1906–1969). In the 1970s, it was transformed into the Park Gravenrode recreational area after it became apparent that excavating it would be too expensive. The hill stands at an altitude of 225 metres above sea level and can be climbed via a staircase. The staircase leads to a platform offering a magnificent view. This makes the staircase a popular tourist attraction.
Longest staircase in the Netherlands
With 508 steps, the Wilhelminaberg staircase is the longest in the Netherlands. The staircase is constructed from prefabricated concrete stair elements and landing slabs. The underlying hill consists of mine rock covered with a layer of soil approximately 1 metre thick. Due to scouring, the staircase had partially subsided and some of the concrete sections were uneven. In some places, the subsidence amounted to between 30 and 60 millimetres. This made the ascent unsafe for pedestrians and sports enthusiasts.
Lifting stair sections
As always, one of our technical advisers carefully assessed the situation. In the case of the Wilhelminaberg, it was decided to underfill the stair sections and lift them using the URETEK FloorLift® method. This restored the load-bearing capacity. The adjacent stair treads that had not subsided were used as a reference point to determine the required height. Thanks to URETEK, the safety of the staircase has been restored and visitors to the area can continue on their way safely.
