Incipient Flow in Silo‐Hopper Configurations

Abstract

A finite element model to analyze the case of incipient flow for cohesionless material in silos is presented. The model is formulated on the incremental principle of virtual work, and is based on small displacement theory. An elastic perfectly plastic material model is used, and wall friction is included in the formulation by the use of a thin layer interface element. The effects of load history are simulated by layering the bulk material in stages during filling and incrementally releasing the outlet forces during flow. A model problem is analyzed and the results for both initial filling and incipient flow cases are compared with classical theories. In addition, design situations involving incipient flow and “locked‐in” stresses are discussed.