Abstract:
In order to improve the energy absorption performance of the anti-impact support for coping with the frequent occurrence of underground impact pressure under the trend of deep mining of coal resources, a multi-cell thin-walled energy-absorbing component with mixed circular and polygonal cross-section is proposed to be applied to the anti-impact support column. Based on the Simplified Super Folding Element (SSFE) theory, the energy dissipation paths of multi-cell thin-walled energy-absorbing components with different cross-sectional shapes and rib layouts are analyzed, the equilibrium equations for energy absorption of energy-absorbing components under axial collapse conditions are constructed, and the prediction equations for the average support reaction force of two types of energy-absorbing components with equal and non-equal thickness are derived. The energy absorption curves, support reaction force curves and buckling deformation patterns of each type of multi-cell thin-walled energy-absorbing members are obtained through axial crush simulation. It is found that the multi-cell thin-walled energy-absorbing components with mixed circular and octagonal cross-section and edge-extended rib layout (type P8-2) have some relative energy absorption advantages, and the influence law of the embedded tube cross-section size, thin-walled tube wall thickness and rib thickness on its energy absorption effect is investigated in depth, namely, the three structural parameters have significant influence on the bending fold pattern and plastic hinge number, and have different and non-simple unidirectional influence on the parameters of energy absorption char-acteristics. The average support reaction force theoretical model based on the SSFE theory is verified to have a high prediction accuracy. Based on the uniform test data, the regression equations of energy-absorbing characteristic parameters on the structural parameters of the components are fitted, and the NSGA-II genetic algorithm is used to optimize the solution, the cross-sectional size of the embedded tube of the multi-cell thin-walled energy-absorbing component is finally determined to be 122 mm, the wall thickness of the thin-walled tube is 2.6 mm, and the thickness of the rib plate is 2.7 mm. Further verified by axial crush simulation and comparative analysis, the results show that the multi-cell thin-walled energy-absorbing component with optimized structural parameters has a better energy absorption effect and a less fluctuation of the support reaction force, which can make the anti-scouring process more reliable. The study provides a useful reference for the design of anti-scouring energy-absorbing components.