Construction progress on the Kriehubergasse gymnasium center

Our construction site in Kriehubergasse in Vienna’s 5th district is impressive due to its unusual construction method for building construction: the gymnasium center is being built using the top-down method.

The quad gymnasium will be built underground in a vacant lot in the historic building block and will connect to the existing school building in the basement.

The necessary excavation support will be carried out on three sides with diaphragm walls and on one side using jet grouting to provide additional underpinning for the existing school. In addition, drilled piles will be used as deep foundations (+ buoyancy control for groundwater up to 7 m high) and auxiliary supports for the top-down method.

These elements support the reinforced concrete slab constructed on top during the construction phase. The slab already includes the skylight openings planned for the finished state and an additional opening for the construction process, such as for removing excavated material and bringing in equipment and materials.

Once the slab has been completed, excavation will begin down to the ground plate of the gyms, which is planned to be approximately seven meters below the upper slab. At half the excavation level, the jet grouted underpinning will be additionally stabilized using prestressed strand anchors for the construction phase, and temporary corner bracing will be installed at the corner of the excavation pit that is subject to the highest loads.

Completion is scheduled for summer 2027, and sports activities can begin in the new gyms in the following fall semester.

Photos: werkraum ingenieure

Plans and Renderings: ARTEC Architekten