Features of silo operation in difficult ge-otechnical conditions

The performance of corrugated-wall steel silos for grain storage under complex geotechnical conditions depends significantly on the silo diameter and the height-to-diameter ratio. A key factor influencing foundation design is the vertical pressure exerted by the grain on the silo bottom, which increases with diameter. Based on pressure levels, all factory-made silos are divided into three groups: small (d = 11–16 m, 80–120 kPa), medium (d = 16–22 m, 120–160 kPa), and large (d = 22–28 m, 160–200 kPa). Each group demonstrates different performance characteristics under weak or collapsible soils. For the first group, natural subsoil or compacted soil cushions may be sufficient even under poor conditions. It has been established that for silos of the second group it is advisable to reinforce weak and subsiding soils or cut through them with pile foundations, especially for the bottom base, or to apply correctly substantiated calculation models of the joint operation of the components of the system “subsidence (weak) soil base – ring foundation – silo gallery – compacted base – bottom plate”. For the third group, construction on a unified foundation slab that supports the silo walls, bottom, and under-silo gallery is recommended. This solution ensures more uniform deformation and reduces the risk of operational problems. The results of surveys and numerical modeling confirm that the second group of silos is most prone to operational complications, especially if geotechnical control is not observed when compacting the backfill under the bottom. A set of recommendations is proposed that take into account the influence of the h/d ratio, the level of loads, and the type of soil base when choosing the type of foundations, which increases the reliability and durability of structures.