This conference paper was submitted for presentation at the NAFEMS World Congress 2025, held in Salzburg, Austria from May 19–22, 2025.

Abstract

The types of aggregates loaded in the dump truck vary from soil or building waste to sand, gravel, and rock, and it is common to load up to 27 tons of these aggregates and repeat loading, transporting, and unloading hundreds of thousands of times. Therefore, it is necessary to predict the dump truck loading box's reliable strength and durability performance in the design stage. Generally, aggregates, such as sand and gravel do not follow hydrostatic pressure conditions due to their behaviors being different from fluids. However, so far, the load calculated by the modified hydrostatic pressure theory has been used to perform static strength analysis on the loading box, so reliability has been slightly insufficient. In addition, the strength of the hydraulic cylinder mounting portion of the loading box and the deformation and strength of the Auxiliary Pannel outside the rear gate of the loading box could not be verified by static structure analysis methods. This method cannot consider the dynamic characteristics of the load due to the behavior of aggregate particles. Therefore, in this study, the dynamic behavior of aggregates was simulated through the discrete element method, and the deformation and strength of the dump truck loading box due to the dynamic load caused by aggregates were predicted when the aggregates were unloaded. In this case, the structural analysis of the dump truck loading box using the finite element method was performed simultaneously with the dynamic behavior of the aggregates. This technique is a DEM-FEM 2-way coupling simulation. At each time step, the aggregate particle transfers the load to the FEM element, and the deformation due to the load is calculated. Then, the behavior of the aggregate particle by the deformed element is updated. Through this iterative calculation, the deformation and strength of the dump truck body due to the dynamic load of the particle can be obtained. In this study, 27 tons of gravel were loaded onto a dump truck, and the dumping process was simulated, and the stress and strain of major parts were analyzed through this. The mass flow rate of gravel during dumping was analyzed to analyze the cause of the major load distribution applied to the auxiliary panel, and a guide for the design of the auxiliary panel was proposed through this. A new reliable and efficient analysis method was proposed by evaluating the strength of the hydraulic cylinder mounting part under a large load when the aggregate is unloaded and the deformation and strength of the Auxiliary panel.