Construction site of the Albrecht-Dürer day-care centre in Halle (Saale) made safe by G.E.O.S. - geotechnical advice on securing a mining sinkhole

At the end of 2019, the G.E.O.S. branch in Halle was commissioned by the building management department of the City of Halle (Saale)'s own daycare centre operation to provide geotechnical advice on securing the site above a mining sinkhole on which the outdoor play areas of a daycare centre are to be built. The development of the property on Albrecht-Dürer-Straße was only approved subject to compliance with the structural engineering requirements of the Saxony-Anhalt State Office for Geology and Mining (LAGB).

The area planned for the new outdoor facilities is a tipping area above a former lignite mine. The need for sinkhole protection resulted from previous ground and surface sinkholes with diameters of up to 3 metres in the immediate vicinity of the construction site.

The services provided by G.E.O.S. included engineering consultancy services for the planning of the sinkhole stabilisation. G.E.O.S. also provided technical support during installation. The sinkhole protection using geogrids was planned and implemented in accordance with the specifications of a design for sinkhole funnels up to a maximum of 3 metres. The geogrids were installed crosswise in state-of-the-art technology.

Taking into account the concerns of officials, nothing was standing in the way of the construction work. The daycare centre was completed and put into operation in 2021. Due to the coronavirus pandemic, the official inauguration took place on 8 October 2021.