![]() However, Rankine’s formula regards the silo wall as smooth, ignoring the friction between bulk material and silo wall, and Janssen’s formula regards the silo as infinite depth and fails to take into account the influence of silo bottom on lateral pressure. For the silo with aspect ratio between 1.0 and 1.5, according to silo specification, the lateral pressure on the silo wall should be calculated simultaneously according to the formulas of the shallow silo and the deep silo based on Rankine’s earth pressure theory and Janssen’s theory, respectively, and the maximum value calculated by the above two methods should be adopted 8, 9. For example, a bolted steel silo that stored 9000 tons of coal ash collapsed after it was first filled due to insufficient consideration of lateral pressure on the silo wall 7. For shallow and circular silo (SCS), when the aspect ratio is between 1.0 and 1.5, the lateral pressure especially the dynamic pressure may destroy the silo if the silo size is large 6, 7. Therefore, the dynamic pressure is the main consideration for the design of the silo. Although the silo structure is relatively simple, the storage material is an interactive particle aggregation with complex mechanical properties of solid and liquid. The idea that the dynamic pressure on the sidewall is greater than the static pressure during concentric discharging has been generally accepted, which may cause the silo’s structural failure and affect the stability of bulk solid handling. ![]() It is widely known that concentric discharging at the silo bottom is the most desirable discharging way 2, 3, 4, 5. Therefore, the safety of the silo is important. Especially in China, about one-third of the grain storage structures use silos. The characteristics of the silo are large storage, easy mechanization, reasonable mechanics and good anti-seismic performance 1, which is widely used in grain engineering, chemical engineering, coal engineering, and so on. Therefore, the modified method of lateral pressure formula is reasonable, which can provide guidance for the safety design of silo structure. The dynamic lateral pressure calculated by the modified method is in good agreement with that of the experimental and simulation, and the relative error is less than 10%. The relative error of the dynamic lateral pressure based on Janssen theory is between 20 and 30%, which is too large. ![]() For the dynamic lateral pressure calculation, Rankine theory is unsafe for the discharging load. The results show that the Rankine’s formula is too conservative for the static lateral pressure, and the results of the modified method and Janssen formula are close to that of the experimental and simulation. The availability of shallow silo and deep silo methods, and the modified method were compared with the experiment and simulation. ![]() This paper proposed a modified calculation method of lateral pressure on the silo wall of SCS, considering the elasticities of silo wall and storage materials. For the shallow and circular silo (SCS), when the aspect ratio is between 1.0 and 1.5, the lateral pressure especially dynamic pressure may cause destruction if the size of the silo is large. ![]()
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