At the beginning of 2013, the construction of a sugar silo with a capacity of 60,000 t was planned on the site of the factory in Kaposvár. The diameter of the ~39 m high, hemispherical structure is almost 60 m. The silo is drained through a 4 m deep tunnel under the structure. The site is geotechnically unfavourable. Up to a depth of 10-12 m from the surface, soft, compressible layers have been deposited, favourable soil zone is located only at a depth of 16-18 m. The groundwater is close to the surface.

Our task was to contribute to the design of the foundation concept and to verify the limit states of the selected solution geotechnically. In the search for an economically and technically optimised solution, the improvement of the upper zone with stone columns and the transfer of the load to the deeper layer with diaphragm barrettes or pile foundation were considered. Taking into account the contractors’ capacities, it was decided to use a pile foundation with CFA piles, which are connected directly to the structure only at the silo perimeter and along the tunnel. The transfer of the load in the inner zones of the silo is ensured by a ~2 m thick granular load transfer layer above the piles.