On the possibility of redistribution of loads from the aggregate in silos as a result of seismic impacts

DOI: 10.37153/2618-9283-2021-4-36-49

Authors:  
Rubric:     Theoretical and experimental studies   
Key words: seismic impacts, silos, aggregate, vibration compaction, precipitation, development of friction forces, calculations, experimental data, placeholder hanging, increased pressure on walls
Annotation:
Based on the calculation justification and analysis of experimental data, it is shown that in silos, as in hydraulic structures of cellular construction, as a result of seismic influences, in addition to inertial mass forces and alternating pressures of the filler on the walls, additional pressures associated with an increase in its hanging on the walls and the redistribution of loads that persist for a certain time may arise. The resulting pressures on the walls can be determined according to the author's formula and for a sand aggregate exceed static ones: 1.57 times – lateral, 1.2 times – vertical, associated with the development of friction forces The reason for the occurrence of load redistribution is the development of friction forces at the walls, which occurs as a result of aggregate precipitation during vibration compaction as a result of seismic influences. This phenomenon can be observed in silos, in which large values of dynamic coefficients arise during fluctuations. Calculations supported by experimental data show that under 9-point seismic impacts, the redistribution of loads with an increase in pressure to the above values can be observed along the entire height in silos with sand aggregate up to 25 m high with a diameter of 3m to 6 m, and in silos with a diameter of 8 m – in the upper part to a depth of 13 m. At 8-point seismic impacts, this phenomenon can occur in silos with small diameters of 3m and 4m with an increase in pressure in their upper part with a depth of 3m to 5m, and at 7-point – it covers only the upper part of structures with a depth of 1...1.5 m, that is, practically absent. Used Books:
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