Dismantling and Logistics Setup

For the construction of the new GLC research and laboratory building in the university district of central Zurich, the existing Hydraulics, Hydrology and Glaciology (VAW) building and the Gloriabar on Gloriastrasse were dismantled. The planned excavation pit is located on a slope that drops away to the south, with its lowest point at around 27 meters deep. Due to the limited space between the excavation pit and the nearby VBZ railway line, a logistics platform is being built over Gloriastrasse before excavation begins from street level.

Braced Excavation Pit Details

The excavation pit is braced with an anchored, contiguous pile wall with nine anchoring points. The bored piles are braced in the rock over a distance of 7 meters using in-situ concrete infill for the moraine layers and shotcrete infill for the underlying molasse. Diaphragm walls positioned 19 meters deep and spaced 7.15 meters apart support the structure, with a protective panel created using the top-down method to shield the bored piles from the subsoil. Further lowering of the excavation pit involves in-situ concrete wall panels anchored with three points.

Foundation Strengthening Near Auditorium

Some parts of the excavation pit are adjacent to the existing Scherrer auditorium, a listed building belonging to ETH Zurich. Its foundation is being strengthened with micropiles, underpinning concrete in small stages, and secured with anchors and nails. Additional structures also utilize the top-down method in certain areas. The project faced significant challenges due to the complex surroundings of the excavation pit and logistics heavily influenced the work schedule.

Excavation Volumes and Materials

The detailed services include the excavation of 80,000 m³ of the foundation pit, including 30,000 m³ in the bedrock. The project used 3,000 meters of bored piles DN800, 33,000 meters of pre-tensioned anchors (approximately 900 pieces), 4,000 m² of in-situ concrete, and 700 m² of shotcrete.

Project Timeline and Management

The construction began in June 2015 and was completed in October 2017. The project was managed by ETH Zurich and IB Immobilien as the building owner and contracting entity, respectively. General management was handled by Befair Partners AG, with architectural design by Boltshauser Architekten and project design by wlw Bauingenieure AG and Dr. Lüchinger + Meyer Bauingenieure AG. ETH Zurich c/o Befair Partners AG managed the construction.