In many Danish cities, construction has changed severely over the last years. We build taller and taller and the buildings often include deep basements with several floors. Deep excavations and dewatering systems are required. However, in a few Danish cities an underground of plastic clay complicates construction even further and influences costs considerably.

Briefly about the project


Across Denmark, dated city and harbour areas are transformed into new and vibrant residential- and business neighbourhoods. Cities flourish, benefitting both inhabitants, tourists and corporations, with renewed vitality. Aarhus is no exception with its large and spectacular construction projects – especially in the port area.

The underground in the port of Aarhus and in the city centre differ from most other cities, because of plastic clay deposits. Plastic clay is to some extent unpredictable, with its relatively unfavourable strength- and deformation properties, due to its unique ability to absorb and give off water. The clay is therefore able to deform and even rise foundations and floor structures.

Plastic clay also presents challenges in other cities in Denmark. In the eastern part of Jutland and western part of Funen, cities like Skive, Randers, Vejle, Middelfart and Fredericia have similar challenges due to the plastic clay.

Fun fact

142 m

The Lighthouse* project was designed as a 142-meter tall tower, which would make it the tallest building in Denmark.

Did you know

Did you know that plastic clay is a very tricky soil to build on? Plastic clay has an ability to absorb and give off water, which means that the clay can shrink and swell.

Did you know

Did you know that Aarhus is one of the oldest cities in Denmark? The borough was granted a municipal charter in 1441, but can be traced back as early as the middle of the 8th century.

Fun fact

Record !

In the summer of 2014, Geo performed a 120-meter record deep CPT study in the port of Aarhus. This is the deepest CPT, Geo has ever performed, in one stroke.

Fun fact


Aarhus is the second biggest city in Denmark. Aarhus is located on the east coast of Jutland.

Geo's role in the project


Construction in Aarhus is booming and Geo is involved in most of the construction projects in both the port of Aarhus and the centre of Aarhus. Intelligent foundation designs are in demand, in order to minimise risk and cost.

  • The Lighthouse* project aims to become the tallest building in Denmark. However, the underground and the foundation of the skyscraper is providing major challenges. Geo has performed geotechnical investigations with very deep CPT’s and borings. One of the geotechnical borings was performed to a depth of 120 metres, which is a local record. Geo also performed three equally deep CPT investigations.
  • ‘AARhus’, designed by BIG, is one of the other high profiled buildings in ‘De Bynære Havnearealer’. Geo performs geotechnical and environmental investigations, as well as consultancy and foundation design concerning plastic clay.

  • Havneholmen, a residential building under construction, will contain some 400 rental flats. Geo has performed geotechnical and environmental investigations and is consultant for the construction in regards to foundation design, execution and dewatering.

  • For Isbjerget, another signature project in the harbour, Geo also performed site investigations, as well as consultancy on foundation design and dewatering.

  • Furthermore, Geo has been involved in other significant construction projects in Aarhus, among others are Z-huset, SHiP, Kvarterspladsen, Pakhusene, Frederiks Plads and Ceres.

Services used in the project
Onshore Geotechnical Consultancy , Drilling
Geotechnical investigations for Lighthouse in the harbour of Aarhus

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