Keller installed about 110 000 meter of Ø800 mm lime-cement columns to stabilize the ground for the new project Drammen Helsepark at Brakerøya in Drammen. The works was partly executed with 3 of Keller's DDSM-rigs at the same time.
The project
Drammen Helsepark will, at completion, consist of seven separate buildings with a combined area of 85 000 m2 near the new Drammen Hospital. The different buildings will house various services like infirmary, hotel, offices, stores, a school, cafe shops, restaurants etc. Kjeldaas AS, was on behalf of Drammen Helsepark AS, contracted to execute the ground works in the project. In connection to this, Keller was awarded the contract to execute the ground stabilizing works with lime-cement columns. The ground in the area consisted of sensitive clay that had to be treated before excavation of the building pit.
The challenge
The challenge in this project was mainly the sensitive clay that had to be stabilized before excavation as well as the big number of columns to be installed in a short amount of time.
The solution
The solution was to stabilize the ground in the building pit with lime-cement columns with a binder content of 100 kg/m3. The lime-cement columns were installed in a rib-system and installed close to the sheet pile walls. To be able to execute the project within the timeframe it was necessary to use 3 of Keller’s DDSM-machines at the same time in different areas of the project. To verify the shear strength in the lime-cement columns, the FKPS-method were used were a steel wing penetrates the columns from the top. The tests showed good results and consequently the amount of binder could be reduced.