Office building in Hamburg

Building use

Office building

Country/Region

Germany

Overview

The building serves as office for 400 employees of the fintech company Serrala. The lot is conveniently located next to the Hamburg airport, in an highly accessible area in close proximity of other office developments. The goal was to build the office with a DGNB Gold Standard certification, a certification protocol active in Germany that looks at the whole life cycle of the building, from construction, through use and future demolition. The DGNB objective was included from the conceptual phase also for the design of the structural system of the building.

Basic information (construction date, number of stories, gross floor area, adopted design code, engineer(s), Contractor(s), etc.)

Construction date: 2023
Number of stories: 5
Gross floor area: 10,000m2
Adopted design code: Eurocodes 0 to 4
Engineer(s): OP Engineers GmbH
Contractor(s): HOCHTIEF Infrastructure GmbH

Issue and/or innovation

Due to the close proximity of the Helmut Schmidt airport runway the use of construction cranes were severely limited. The solution adopted makes use of small and lightweight elements that can be installed with a movable crane, directly from the truck, without the need to store them on the ground and use large machinery on site. This is also possible considering the velocity of construction with about 8 minutes needed to install each column with 3 workers.

Reason for composite solution

The specific – patented – solution was chosen for the facility and speed of construction, requested by the client and it involved no cranes. It allowed the construction of 10.000 square meters of composite structure in 7 months. Another important feature for the adoption of a composite structure was the use of sustainable features of steel and concrete composites and in particular the availability of Environmental Product Declarations for many of the pre-fab components of the structure.

Specific solution/technical details

Columns have been built using centrifugal concrete columns, to allow smaller profiles thanks to the much higher amount of rebars that can be included and the reduced porosity of the concrete. Beams are prefabricated composite beams produced by the company Tecnostrutture. The beams are loadbearing even before the final concrete pour, which allows a much faster construction schedule and avoids the use of scaffolding and temporary supporting elements. Floors have been created using prefabricated hollow core prestressed concrete tiles, which also gave a fundamental boost to the speed of construction.

Impact or effectiveness

Certification goal achieved; limited use of cranes obtained thanks to the adopted solution. The use of a composite structure allowed according to the design company, a saving of 50% concrete and 75% steel if compared to conventional concrete or steel structures respectively. The use of products coming from the company Tecnostrutture, that has an Environmental Product Declaration available for most of its product, allowed to certify that 93% of the steel comes from recycled material, an important aspect to attain the DGNB Gold certification requested by the client.

References / Technical Papers Content

Foraboschi P., 2016. “Versatility of steel in correcting construction deficiencies and in seismic retrofitting of RC buildings” J. of Building Engineering, 8 107-122 http://dx.doi.org/10.1016/j.jobe.2016.10.003