Abstract: In the loading process of loader, the generation of dense core would caused excessive resistance of horizontal loading, resulted in the decline of loading performance and increased of energy consumption. Aiming at this problem, the horizontal shovel resistance in dense core stage was studied. Firstly, the resistance variation of horizontal shoveling stage was analyzed by using the theory of compact core, then the horizontal resistance of the bucket was obtained through the automatic shovel loading test of the loader, and the existence of dense core was verified. Then, the method of avoiding dense kernel was studied according to the experimental data, and the fuel consumption was compared in the stage with or without dense core when the depth range of the bucket was the same. Finally, the accuracy of the theoretical model and EDEM simulation was verified by experiments. The results show that controlling the insertion depth of the bucket is less than 202mm can avoid compacting core. Within the same range of shoveling depth,the fuel consumption per unit in the compactioncore stage is 1.9~3.34 times higher than that in the non-compaction-core stage. The error of the slip surface theoretical model and EDEM simulation is less than 7%, both of which can accurately calculate the horizontal shovel resistance.

Key words:  loading and unloading machinery; loader;horizontal shovel resistance;dense core theory;loading process;EDEM simulation;energy consumption