AU 20 sheetpile retaining walls as support for excavation at Munich Airport
The construction of an office building near Munich Airport called for a watertight cofferdam to be built. The groundwater level at the building site was 0.5 to 1 meter below the surface. To avert technical or economic problems, topsoil was stripped to a depth of about 0.5 meters, and sheet piles were installed. To ensure compliance with the fast-track construction schedule, the contractor opted for the most efficient solution: a steel sheet pile structure using the economical ProfilARBED AU 20 sections.
The AU 20 was the first section in the hot-rolled AU series. Since, at 750-mm, it is 25% wider than conventional sheet piles, it made for faster driving and superior watertightness due to the lower number of interlocks per meter of wall. No further sealing of the Larssen interlocks was needed. Additional savings of up to 10% on the quantity of steel (relative to a comparable PU 20 section) made the sheet pile wall very economical indeed. The 11-meter-long sheet piles were driven into the Tertiary soil layers without any problems; in fact, driving performance was outstanding.