LOADS IN MODEL GRAIN BINS AS AFFECTED BY FILLING METHODS

Measurements of wall and bottom loads in flat-bottom model bins have s hown the influence of filling methods and wall surface on wall loads a nd the static-to-dynamic load shift. Four spout-filling methods, at ce nter and eccentric locations, sprinkle filling, and uniformly filling through an annular ring near the bin wall, were evaluated. Three types of bin walls were tested for each filling method smooth galvanized st eel, corrugated galvanized steel, and smooth steel covered with abrasi ve cloth. Soft and hard winter wheats were used in the experiments. Th e static wall load to total grain load ratio (SWL / TGL) and the dynam ic-to-static wall load ratio (DSR) were found to be influenced by the filling method. In general, a higher SWL / TGL resulted in a lower DSR . Sprinkle filling produced lower SWL / TGL values on the smooth wall and higher values on the rough and corrugated walls. The ratio of the wall to total grain load at the start of discharge was highest for the first opening of the discharge gate as compared to two successive gat e openings (each after 30 min of rest). The filling method and the typ e of wheat significantly influenced the negative friction force on the smooth wall bin. Negative friction force values were highest for the top filling methods. A negative friction force was not observed for co rrugated and rough wall bins.