Cologne

WDR Filmhaus renovation

GEWI piles for the retrofitting of the foundations on the third basement level.

Retrofitting foundations within an existing building

For the structural upgrading and refurbishment of the building, a total of 73 GEWI piles were installed during the first construction phase between late November and mid-December 2019. Further construction phases followed in 2020. The work was carried out inside the existing building and had to be adapted to the existing load-bearing structure as well as the spatial constraints.

Pile foundation in confined spaces

The micro piles were installed in the building’s third basement level. In some places, the available working height was only around 3 m. In addition, there were numerous load-bearing structural elements and columns within the work area that had to be preserved during the construction work. In some areas, the distance between the drilling axis and the existing wall was as little as 25 cm.

Adapting the drilling technique to the existing structure

For the works, the drilling rig was adapted to the available space. To reach individual drilling points, openings were cut into partition walls at specific locations. These openings were created in accordance with the requirements of the existing building structure. This meant that the drilling equipment’s range of movement was restricted in some areas, a factor that was taken into account when planning the work sequences.

Bringing the equipment into the existing building

The space available for site facilities was limited due to the inner-city location and the building’s geometry. The drilling rig was therefore lifted into the building via an existing opening using a crane. Whilst the pile foundation work was underway, other trades were also carrying out work inside the building. The construction sequences were co-ordinated accordingly.

GEWI piles for load-bearing of the structure

The GEWI piles installed reached depths of up to 13 m. The boreholes were drilled to a diameter of 178 mm. The load-bearing elements used had diameters ranging from 32 mm to 50 mm. The retrofitting foundations complement the existing load-bearing structure and form the basis for the conversion and refurbishment works at the WDR Filmhaus.

Basis for the comprehensive refurbishment

The installation of the GEWI piles laid the groundwork for the subsequent phases of the comprehensive refurbishment. The retrofitting foundations were carried out within the existing building and were tailored to the structural requirements of the project.