新型泥石流柔性防护体系冲击动力响应分析

Dynamic response analysis for a new type of debris flow flexible protection system

为了减轻泥石流大石块造成的灾害,提出了新型泥石流柔性防护体系。考虑不同加载工况,运用有限元软件ANSYS/LS-DYNA对防护体系进行抗泥石流中大石块冲击的数值模拟,研究了冲击物质量、速度,柔性防护体系的钢筋直径、网格尺寸对防护体系动力性能的影响。结果表明:冲击物质量或速度增加,体系的冲击力明显增大,总能量增加且转化为内能效率增大,冲击处位移明显增大。加大钢筋的直径后冲击力增加,体系不失效情况下内能转化率减小,位移减小;随着网格尺寸增大,冲击力减小,而内能转化率略微增大,冲击点处位移明显增大。因此建议在实际应用中应合理设计拉索直径及网格间距。

To reduce the disaster caused by the rock of debris flow,a new type of debris flow flexible protection system is proposed.Considering the different loading conditions,the finite element software ANSYS/LS-DYNA was used to simulate the different conditions of the protection system,including the quality and speed of the boulder impact,flexible protection of steel bar diameter and grid size.The results show that as the impact quality or velocity increases,the impact force increases obviously,the total energy increases and the internal energy efficiency increases,and the displacement of the impact increases significantly.As the diameter of reinforcement increases,the internal energy conversion rate and the displacement decrease.As the grid spacing increases,the impact force decreases,while the internal energy conversion rate increases slightly,the displacement of the impact points increases significantly.Therefore,it is suggested that the cable diameter and grid spacing should be reasonably designed in practical application.