抗8000 kJ能级落石冲击被动柔性防护网设计  

Design of passive flexible barrier against rockfall impact with 8000 kJ energy level

作　　者：吴昊 吴逸凡 马亮亮 WU Hao;WU Yifan;MA Liangliang(College of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092

出　　处：《爆炸与冲击》2025年第3期168-188,共21页Explosion and Shock Waves

基　　金：国家自然科学基金(52378526)。

摘　　要：采用数值模拟方法开展了8000kJ能级被动柔性防护网的抗落石冲击分析与设计工作。首先,基于显式动力学有限元软件ANSYS/LS-DYNA对典型被动柔性防护网单环和三环环链拉伸试验、网片顶破试验以及2000kJ能级落石冲击足尺防护网试验进行数值模拟复现,通过与网环最大破断力、破断位移和破坏特征、落石冲击全过程以及防护网钢丝绳内力时程等试验数据进行对比,验证了所采用数值模拟方法的可靠性。然后,分析了钢柱倾角、跨距、高度以及消能装置规格等参数对落石冲击下防护网动力行为的影响,结果表明:消能装置规格是控制防护网内力与位移的关键参数;钢柱倾角建议取10°;增大钢柱跨距会降低结构的面内刚度,而对横向锚固力的影响较小;增加钢柱高度会显著提升柱底支反力;改变钢柱高度和跨距需同时合理调整各钢丝绳的锚固位置。最后,通过调整防护网几何尺寸、消能装置规格和添加横向辅助支撑绳等措施给出了2种8000 kJ能级防护网设计方案,均通过EAD 340059-00-0106标准检验。The protection level and domestic standard test level of commonly used passive flexible barriers against rockfall impact are not higher than 5000 kJ,while bridges in mountains and other important transportation infrastructures are facing rockfall disaster threats with higher impact energy levels.Considering that the design method for passive flexible barriers with higher impact energy levels is lacking,to provide a feasible and reliable tool for the infrastructure engineers,the analysis and design of 8000 kJ-level passive flexible barrier against rockfall impact were carried out at present based on the numerical simulation method.Firstly,by adopting the explicit dynamic software ANSYS/LS-DYNA,quasi-static tests,including the tensile test on single wire ring and three-ring chain,net puncturing test,and the dynamic impact test,i.e.,2000 kJ rockfall impacting the full-scale passive flexible barrier,were numerically reproduced,and the reliability of the numerical simulation method was fully verified by comparing with the test data,i.e.,the maximum breaking force and breaking displacement of the wire ring and its failure characteristics,the whole impact process of rockfall,and the cable force-time history curves,the influencing factors,i.e.,the inclining angle,span,and height of the steel post and different specifications of energy dissipating devices ranging from 50 kJ to 70 kJ,on the dynamic behavior of the passive flexible barrier were further analyzed.The results show that the specification of the energy dissipation device is the most critical parameter controlling the internal force and displacement of the passive flexible barrier.The inclining angle of the steel post is recommended to be 10°.An increase in the post spacing can reduce the in-plane stiffness of the structure while having less effect on the transverse anchorage.An increase in the post height will cause a significant increase in the support reaction force at the post bottom.A reasonable adjustment of the anchorage position of each wire rope is requ

关 键 词：被动柔性防护网 落石冲击 参数影响 结构设计 

分 类 号：O347.2[理学—固体力学] TU311.41[理学—力学]