THE FOUNDATIONS OF THE RHINE BRIDGE FUSSACH-HARD (AUSTRIA)-PPT Presentation

PPT Presentation

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The new Fussach–Hard Rhine Bridge in Austria was built to meet modern structural and traffic requirements and support the Swiss–Austrian RHESI flood-control project. RHESI aims to increase the Alpine Rhine’s discharge capacity from 3,100 to 4,300 m³/s, protecting a valley of approximately 300,000 residents from extreme flooding.<br /><br />The 255.6 m bridge is a four-span composite structure supported by three piers. Its foundations had to accommodate challenging ground conditions, including very soft lacustrine clays and highly compressible soils extending to depths of 50 m. Shallow foundations and end-bearing bored piles were unsuitable, so designers used downward-fanned pile groups combining vertical and inclined, floating friction piles to distribute loads and control settlement.<br /><br />The project used externally grouted ductile iron piles, selected for their adaptability, rapid installation, low vibration, and full-displacement installation method. A full-scale pile-group load test informed the design. Despite a short winter construction window due to flood risk, one six-person crew installed approximately 22.8 km of piles for the bridge and a further 17.1 km for ancillary structures between September 2020 and March 2021, averaging about 250 m per day. The substructure was completed in April 2021, and the bridge opened to traffic on November 18, 2022.<br /><br />The presentation also assessed environmental impact using Environmental Product Declarations and a carbon calculator. The 1,816 bridge piles, totaling 39,920 m, were estimated to produce 2,340 tonnes of CO₂-equivalent emissions. Pile material accounted for 66% of the calculated global-warming impact, cement for 31%, and other sources for 3%. Removing and recycling the upper 5 m of 23% of the piles after 100 years could potentially reduce emissions by 576 tonnes of CO₂-equivalent.

Keywords

Fussach–Hard Rhine Bridge

Austria

RHESI flood-control project

Alpine Rhine

composite bridge

pile foundations

lacustrine clays

ductile iron piles

Environmental Product Declarations

carbon emissions