At the end of the lecture period, students on the Civil Engineering and Subsurface Engineering degree programmes took part in the laboratory practical course on the use of concreteite suspensions in horizontal directional drilling (HDD) in the bentonite laboratory of the Chair of Tunneling and Construction Management with active support from the field.

Mario Bruns, Beermann Bohrtechnik GmbH, reported on the horizontal drilling work to realise the DolWin6 grid connection. Electricity generated by the wind farms on the associated offshore platform in the North Sea is transported to the mainland in Hilgenriedersiel via the island of Norderney using a 45 km long submarine cable. The electricity is then transmitted further to the transfer point in Emden. To protect the sensitive natural area in the Lower Saxony Wadden Sea National Park, strict restrictions were imposed on the cable route via Nordeney, which posed particular challenges for horizontal drilling work for protective pipes up to 1,300 metres long.

Rainer Breig, R. Breig Tiefbau UG, is an expert in horizontal drilling in rock/solid rock and brought various rock drilling heads and a standard surveying device using the walk-over method to the laboratory. A vivid presentation of impressive projects rounded off the presentation.

Under the guidance of Ferenc Kriwitzki, Technical Professional at Baroid IDP, the students were not only able to get to know and try out the most common test methods for the rheological parameters of bentonite slurries, but also went in search of certain contaminants that massively impair the quality of suspension samples.

All in all, the participants enjoyed an exciting day in the laboratory with intensive discussions and new insights for all involved.