Shaft with great freezing depth, Rheinberg Shaft

Planned and constructed a shaft with a great freezing depth, having a peripheral freezing diameter of 22 m and a freezing depth of 526 m. 

The Rheinberg freeze shaft was designed as a material, rope winding and extraction ventilation shaft. With a refrigeration pipe end depth of more than 526 m, it is one of the deepest freeze shafts in the world. The shaft is characterised by the innovative, combined composite shaft lining system consisting of a definitive static bearing outer lining and static bearing reinforced concrete steel compound lining with asphalt backfilling.

The caisson technique was used to construct the first 20 m of the shaft. As far as the inner lining in the freeze shaft part is concerned, there is a 20 cm thick asphalt joining layer, an 18 mm thick water-tight welded steel sheets, reinforced concrete lining and an inner steel sheets 15 - 82 mm thick.  A concrete cylinder with open ring joints was installed in solid and non-water-bearing rock.