EN 
DE Difficult conditions due to old buildings
GMSH is planning the construction of a new institute building for the civil engineering and architecture degree programmes on a car park at Kiel University of Applied Sciences in Schwentinestraße / Grenzstraße. The scope of services includes a ground investigation to assess the soil, a foundation recommendation and details of the earthworks and shoring work. Six small pile drillings and seven pressure soundings were planned in May 2023 to determine the soil structure.
Through historical research, it was known that the site had been built on since the end of the 18th century. From around 1876 to 1984, the site was used by the Howaldtswerft shipyard. Most of the buildings were destroyed during the Second World War and rebuilt in the 1950s.
Previous investigations of contaminated sites from 2020 had already identified massive drilling obstacles in the form of base plates and foundations across the entire investigation area. It was also known that two air raid shelters from the Second World War were located underground. Based on the results of the historical research and the site plans available to us, the planned exploration points were placed between the existing foundations and air raid shelters.
In the run-up to the subsoil investigations, the planned drilling points were surveyed by an explosive ordnance clearance service, as the entire investigation area was suspected of containing explosive ordnance. In the course of these deep soundings, massive drilling obstacles were encountered on the investigation area, which could not be recognised in the existing plans.
The subsoil investigations proved to be correspondingly difficult. The explorations had to be cancelled and relocated several times due to the obstacles in the subsoil. With good luck, the drilling team managed to carry out four small percussion drillings and three pressure soundings. The project shows us that despite existing information about the history of the site and plans of old buildings, it can never be ruled out that there are other unknown obstacles in the subsoil and that these will lead to more difficult conditions during the investigations.
