Versmannkai East, site clearance BF 102-110

The construction sites 102, 105, 108 and 110 were located in a former water area that had not yet been explored. The aim of the work was to check the unexplored construction sites with suspected unexploded bombs down to a depth of -9.5 m below sea level (-15 m below ground level) by means of borehole probing and to achieve clearance.

In the run-up to the exploratory work, existing quay installations (quay slab, concrete spar, sheet pile wall) had to be demolished in some areas. The sheet pile wall was only partially removed. The soundings were carried out by means of a triaxial magnetometer, supplemented by an active method (here 4R-EM) and borehole georadar in order to determine the

The aim was to keep civil engineering costs for the recovery as low as possible. The recovery at greater depths was carried out by means of large-hole drilling and diving operations.

The terrain was adjusted by backfilling the excavation pits and modelling to contractually agreed transfer heights.