上下双层浅圆仓中心卸料的动态效应分析

Dynamic Effects Analysis of Unloading in the Center of Upper and Lower Double-story Squat Silo

上下双层浅圆仓作为一种新型粮食储藏结构,既可以保证储粮品质,又具有节约用地、节能减碳、机械化程度高等优势。采用离散元与有限元结合的方法,构建了上下双层浅圆仓中心卸料过程粮食颗粒与仓壁之间动态响应的数值分析模型,利用实验与缩尺模型相结合的方法验证了缩尺方法的有效性;分别将缩尺模型数值分析与理论计算结果进行对比,验证了数值方法的可行性;进而对上下双层浅圆仓中心卸料过程粮食-仓体的相互作用进行了分析。结果表明:中心卸料过程中上下层均出现了侧压力突增和震荡的现象,且在越接近每层仓壁中间位置处,超压系数越大;粮食-仓体共同作用后上下层仓壁的应力均在距离仓壁底部1/4处达到最大。本文可为上下双层浅圆仓的结构设计提供技术支持,有利于其推广应用,具有重要的工程应用价值。

As a new type of grain storage structure,the double-story squat silo(DSSS) can ensure the quality of grain storage,but also has the advantages of land saving,energy saving and carbon reduction,and high degree of mechanization.In this paper,the method of coupling discrete elements and finite elements was adopted to construct a mathematical analysis model of the dynamic response between grain particles and the silo wall during the central unloading process in a double-layer shallow round silo(DSSS).The validity of the scaling method was verified by combining experimental tests with the scaling model.Numerical analyses of the scaled-down model were compared with theoretical calculations to confirm the feasibility of the numerical methods,and the grain-silo interaction during the central unloading of the DSSS was investigated.The results showed that both the upper and lower layers exhibited a sudden increase in lateral pressure and oscillation during the unloading process,with a larger overpressure coefficient and a greater tendency for overpressure to occur in the middle of the silo wall.The stresses in both layers of the silo wall reached their maximum at 1/4 of the distance from the bottom of the silo wall when considering the grain-silo interaction.This study has provided technical support for the structural design of DSSS,facilitating its promotion and application,and had significant engineering implications.