Prediction of initial stresses in hoppers

In the seventies MOTZKUS published an approach for predicting initial stresses in hoppers (filling stresses; stresses during filling and before discharging). In the present paper a short description of MOTZKUS' approach is given containing all the equations necessary for its application. Stresses calculated with MOTZKUS' approach have been compared to experimental data and to results of further approaches (e.g. WALTERS). Finally a discussion of MOTZKUS' assumptions follows.