Abstract: With the rapid development of silo,the unloading with side wall is more and more applied to practical engineering.It is necessary to optimize the design of side wall unloading granary and to explore which kind of silo is the most suitable for unloading with side wall.Therefore,the method of numerical simulation in combination with real-silo experiment was used to investigate the static and dynamic lateral pressure of the silos with different diameters (1.1 and 2.2) in the two side discharge modes,the distribution of maximum dynamic pressure,and to compare the overpressure coefficient.The results showed that the dynamic side pressure change of the shallow silo wall was relatively moderate and the overpressure coefficient was relatively small and the safety was better,compared with the deep silo wall.Its maximum overpressure coefficient was 1.51,and the overpressure coefficient was mostly distributed between 1.05 and 1.2.The maximum overpressure coefficient was 1.58 and the overpressure coefficient was between 1.3 and 1.5.