Experimental and numerical studies on the effect of ballast-flying phenomena on glass/epoxy composite materials applied to lightweight bogie frame for urban trains

초록

This paper describes the experimental and numerical simulation results on the material degradation of glass/epoxy composites applied to bogie frames for urban trains due to ballastflying phenomena. The test specimens were subjected to low-velocity impact with energy levels of 5J, 10J and 20J, and the impactor was designed to have various ballast shapes such as sphere, cube, and cone to simulate the ballasted track environments. After impact loading, the residual compression strength was measured to investigate the degradation of mechanical properties of composite materials for application to bogie frame. An explicit finite element analysis based on LS-DYNA 3D was focused on numerical simulation of indentation damage area and low-velocity impact responses on laminate composites. The results showed that the damage area and the degradation of residual compressive strength after impact for laminate composites was increased with increase of impact energy for all ballast shapes and was particularly most influenced by ballast shape of cone. Also, good agreement was obtained between numerical and experimental results.