Coupled FEM-DEM for determination of payload distribution on Tipper load body

Tippers used for transporting blue metal, construction and mining material is designed with different types of load body to suit the material being carried, capacity and its application. Structural strength verification of load body of tipper is conducted using FEM, by modelling forces due to payload as a pressure function on the panels of the load body. Determining the pressure function on panels is a challenge owing to the complexity of modelling large volume of granular payload using conventional FE methods. Hence, typically the spatial variation of pressure is assumed. The Discrete Element Method (DEM) allows the modelling of granular materials such as gravel, wet or dry sand, coal, etc., taking into account its flow and interaction with the structure holding them. DEM has the ability to numerically calculate displacements and rotations of finite particles. Also, automatically perform contact detection for particle assembly. DEM uses a discrete approach that is very well suited for modelling the bulk behavior of materials. This capability of DEM can be used for prediction of force/pressure distribution on the load body panels. In this paper, coupled FE-DEM is used for determining pressure distribution on loading surfaces of a tipper body structure of a heavy commercial vehicle during loading, unloading and transportation. This pressure is mapped onto the load body panels for structural verification. Also, the model is used for computing the CG of the granular bulk material which is then used for in full vehicle analysis to estimate wheel reaction forces.