Customer: Hamburg, Office for urban development and environment, Dept. for construction and operation, Dept. flood control measurements
Construction period: 09.2007 – 05.2008
Location: St. Pauli, Hamburg
Country: Germany

The flood control measurements at the St. Pauli landing bridges are being replaced as part of the flood control program of the city of Hamburg. A new and combined sheet pile wall will be put ahead of the existing sheet pile wall and anchored with a total of 64 pre-stressed injection piles. A max. distance of 25 m exists between the existing quay wall and the pontoon system placed ahead of it. This pontoon system will carry the entire construction equipment (drilling and material pontoons). The influence of the tides will be a particular challenge for the construction of the pre-stressed injection piles. Every 6 hours flood and ebb come and go. The repeated inflow and outflow of water results in tidal streams and require particular attention during the installation of the pre-pressed injection piles. A difference of about 3.60 m exists between the average water level of a flood and ebb. Drilling can occur during ebb only. This leaves a small window for the installation of the 47°-slanted, repeatedly coupled pre-stressed injection piles at the landing bridge St. Pauli for the flood control measurements of the city of Hamburg.

During the first construction period (September to October 2007), 64 double-corrosion protected small bore piles (diameter 63.5 mm) will be installed (with a length between 17 and 31 m). The pre-stressed injection piles must be extended to their final length of 20 to 35 m once the combined sheet pile wall has been installed.

Foundation engineering measurements
64 small bore piles with a diameter of 63.5 mm and a length between 17 and 31 m