Dynamic characteristics of column supported vertical silos under different grain storage conditions

Vertical silo is a type of container widely used in industrial and agricultural storage, transportation, and grain storage. According to its supporting structure, it can be divided into column supported and cylindrical supported types. As a modern grain storage warehouse type, column supported vertical silos have a small footprint, large storage capacity, and complete grain receiving, distribution, storage, cleaning, weighing, and automatic control functions. Different storage conditions have a significant impact on the dynamic characteristics of column supported vertical silos. To reveal the influence of grain dispersion on the dynamic characteristics of column supported vertical silos, an organic glass silo model with a scale ratio of 1:25 was designed and made based on an actual column supported vertical silo design. Vibration table modal tests, finite element numerical analysis, and natural frequency theoretical calculations were conducted under four storage states: empty, half, three-quarters, and full. The research results indicate that different grain storage conditions have a significant impact on the natural frequency of the column supported vertical silo test model. As the grain storage state changes, the natural frequency decreases significantly, and should be considered in structural design; The damping ratio is the smallest in an empty warehouse state, and it increases by 42.65% in a full warehouse state compared to an empty warehouse state. The more existing grain is stored in the warehouse, the greater the increase in damping ratio and the more obvious the shock absorption and energy consumption effect; There is a significant difference between the torsional stiffness of the finite element model and the first two translational stiffness. Compared with the first two periods, the natural frequency of the third order of empty, half, three-quarters and full grain storage conditions increased by 27.2%, 37.27%, 39.93% and 40.09% respectively; The average error between the first-order natural frequency of the finite element model and the experimental value is 5.1%. The constructed finite element model is relatively reasonable, providing a reasonable numerical simulation method for structural dynamic response analysis and structural design; The simplified three particle series multi degree of freedom elastic dynamic model accurately calculates the natural frequencies of column supported vertical silos under four storage conditions, with an average error of 5.6% between experimental and theoretical values. This study can provide reference for the calculation of dynamic characteristics of column supported vertical silo structures, and provide theoretical basis and experimental basis for their seismic performance design.