Bin loads induced by eccentric filling and discharge of grain

Wall loads were measured in a corrugated-wall model grain bin 2.44 m in diameter and 7.3 m high filled with wheat to a HID ratio equal to 2.0. The model bin was filled either centrally or eccentrically through a chute located along a radial line, coinciding with one of the major axis of the bin, at eccentricity ratios of 0, 0.5, or 0.75. The eccentricity ratio (ER) is defined as the ratio of the distance from the center of the bin to either the filling location or the discharge gate divided by the radius of the bin. The model bin was unloaded either centrally or eccentrically through discharge gates located at ERs of 0, +/-0.5, or +/-0.7. For both an ER of 0.5 and 0.7, two different eccentric discharge gates were used, located on opposite (plus or minus) sides of the bin on a major axis that was parallel to the filling axis. For experiments involving centric filling followed by eccentric unloading, a maximum wall moment of 11.2 kN-m was measured. For experiments involving eccentric filling followed by eccentric unloading, the mutual location of the filling and discharge gates either magnified or reduced the variation in stress within the bin and the resulting moment carried by the walls. For experiments in which the location of both the filling and discharge gates were on the same side of bin, a maximum wall moment of 17.5 kN-m was measured. For tests in which the filling chute was located on the opposite side of the bin from the discharge gate, a maximum wall moment of 3.2 kN-m was measured.