Deep foundation contractor Bauer Spezialtiefbau constructed the four test piles, which are up to 111.4m long and 1,850mm in diameter. They are for the 244m-high Elbtower, which will be Germany’s third-tallest skyscraper and will form part of a 157ha project to redevelop former harbour and industrial areas in the HafenCity district of Hamburg.
The Elbtower’s foundations will rest on long piles to transfer the load to a deep load-bearing soil layer and prevent long-term settlement at the site on low-load-bearing ground near the Elbe River.
Fugro developed the load-testing and measurement technology for the pile-testing programme. The company said its in situ load testing allows clients to verify and potentially optimise the foundation design without the need for the costly and time-consuming installation of the reaction piles used in conventional testing.
The company also fitted what it claimed are the longest-ever thermal integrity tests strings in the rotary bored piles, which had concreted lengths of over 111 m, to verify the structural integrity of the constructed sections.
Fugro’s project manager Hauke Sychla said: “The bi-directional load-testing results and comprehensive pile instrumentation provided by Fugro will help our client and the design firm to understand the ground’s deformation behaviour and the piles’ bearing capacities to design a safe and cost-effective foundation design for the Elbtower.”
The design is by David Chipperfield Architects and the project is being developed by Austrian real estate company Signa Prime Selection.