Hafencity Hamburg
BGW and VBG Prevention Centre
Hamburg, Germany / 04.2019 - 12.2020
The joint prevention centre of the German Social Insurance Institution for the Health and Welfare Services (BGW) as well as the German Social Insurance Institution for the Administrative Sector (VBG) is being built right next to the Elbe bridges in Hamburg. The building has a gross floor area of around 42,000 m² and will be used for initial and further training programmes, consulting services, training courses and specialist events. As part of a joint venture, PORR special civil engineering was responsible for the construction of the turnkey construction pit, including shoring, DSV sealing slabs and pile foundations. The scope of work included bored pile walls, soldier pile shoring, back anchors, internal bracing, a reinforced concrete base as well as the construction of 840 Partial displacement bored piles.
Facts & Figures
Company
PORR Spezialtiefbau GmbH
Type
Turnkey construction pits, Sealing slabs, Foundations
Runtime
04.2019 - 12.2020
Turnkey construction pits and pile foundation works in Hamburg’s HafenCity
Construction pit and pile foundations for the Prevention Centre
PORR special civil engineering constructed a total of 840 Partial displacement bored piles for the building’s foundations. The construction pit shoring consisted of several shoring systems adapted to the local site conditions. These included bored pile walls with concrete head beams and internal bracing, soldier pile shoring with double-layer back-anchoring, as well as DSV sealing slabs in the deepest part of the construction pit. The system was supplemented by a reinforced concrete base.
Special civil engineering in Hamburg’s HafenCity
The construction pit is located in the HafenCity area of Hamburg, outside the main dyke line. The site conditions are characterised by fluctuating groundwater levels as well as challenging ground conditions. The detailed design was carried out by PORR special civil engineering planning. To support construction preparation, a three-dimensional model of the construction pit was created. The 3D modelling included, amongst other things, a collision check for the anchors and served as the basis for coordinating the construction sequences.
Bored pile walls and internal bracing in the vicinity of the underground station
Due to the immediate proximity to the Elbbrücken underground station, the excavation was carried out in coordination with Hamburger Hochbahn. To stabilise the eastern side of the construction pit as well as the deep section towards the Elbe, a reinforced concrete bored pile wall covering an area of approximately 1,950 m² was constructed. The wall was braced using inclined pipe struts within the excavation pit. Before the start of the specialist civil engineering works, existing obstacles such as old sheet pile walls and foundation remains were removed by means of clearance drilling.
DSV sealing slabs in the groundwater zone
Parts of the construction pit lay below the water table. To waterproof the base of the construction pit, sealing slabs were therefore constructed using the jet grouting method (DSV). The combination of bored pile walls, internal bracing, soldier pile shoring, back-anchoring and DSV sealing slabs formed the foundation for the construction of the construction pit under the site-specific conditions of HafenCity Hamburg.
The foundation for the new prevention centre
By excavating the construction pit, constructing the jet-grouting sealing slabs and installing the pile foundations, PORR special civil engineering laid the groundwork for the new construction of the BGW and VBG prevention centre at the Elbe bridges in Hamburg. The special civil engineering works formed the basis for the subsequent structural works on the building complex.
