抗8 000 kJ能级落石冲击被动柔性防护网设计

吴昊; 吴逸凡; 马亮亮

doi:10.11883/bzycj-2024-0150

抗8 000 kJ能级落石冲击被动柔性防护网设计

doi: 10.11883/bzycj-2024-0150

同济大学土木工程学院，上海 200092

基金项目: 国家自然科学基金（52378526）

详细信息

作者简介:
吴　昊（1981－　），男，博士，教授，wuhaocivil@tongji.edu.cn

通讯作者:
马亮亮（1994－　），男，博士，博士后，24310004@tongji.edu.cn

中图分类号: O347.2; TU311.41
计量
- 文章访问数: 155
- HTML全文浏览量: 38
- PDF下载量: 62
- 被引次数: 0
出版历程
- 收稿日期: 2024-05-23
- 修回日期: 2024-07-11
- 网络出版日期: 2024-07-15

Design of passive flexible barrier against rockfall impact with 8 000 kJ energy level

College of Civil Engineering, Tongji University, Shanghai 200092, China

摘要

摘要: 常用抗落石冲击被动柔性防护网的防护能级和国内标准检验能级均不高于5 000 kJ，而山区桥梁等重要交通基础设施常常面临更高冲击能级落石灾害的威胁。采用数值模拟方法开展了8 000 kJ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2 000 kJ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°；增加钢柱跨距会减小结构的面内刚度，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8 000 kJ能级防护网设计方案，均通过EAD 340059-00-0106标准检验。
- 被动柔性防护网 /
- 落石冲击 /
- 参数影响 /
- 结构设计
Abstract: The protection level and domestic standard test level of commonly used passive flexible barriers against rockfall impact are not higher than 5 000 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 8 000 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., 2 000 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 required when the post height and spacing are changed. Finally, based on the results of parameter analysis, two design schemes for a passive flexible barrier against 8 000 kJ rockfall impact were given by adjusting the geometry of the structure, the specification of the energy dissipating device, and the addition of transmission support ropes. Both of them passed the test of the European standard EAD 340059-00-0106.
- passive flexible barrier /
- rockfall impact /
- parameter influence /
- structural design

HTML全文

图 1 防护网准静态试验与足尺冲击试验

Figure 1. Quasi-static and full-scale impact tests of barrier

下载: 全尺寸图片幻灯片

图 2 钢柱细部构造

Figure 2. Detailed diagrams of steel posts

下载: 全尺寸图片幻灯片

图 3 减压环照片及简化性能曲线

Figure 3. Photograph and simplified performance curve of the brake ring

下载: 全尺寸图片幻灯片

图 4 典型网片组成及建模^[22]

Figure 4. Composition and modeling of typical net^[22]

下载: 全尺寸图片幻灯片

图 5 消能装置梁单元的工程应力-应变曲线

Figure 5. Engineering stress-strain curve of beam element of energy dissipating device

下载: 全尺寸图片幻灯片

图 6 有限元模型

Figure 6. Finite element models

下载: 全尺寸图片幻灯片

图 7 滑移接触

Figure 7. Sliding contact

下载: 全尺寸图片幻灯片

图 8 单环网格敏感性分析

Figure 8. Mesh size convergence analysis of single-wire ring

下载: 全尺寸图片幻灯片

图 9 网环力-位移曲线和破坏模式的预测与试验结果对比

Figure 9. Comparisons of predicted and experimental force-displacement curves and failure modes of wire rings

下载: 全尺寸图片幻灯片

图 10 典型时刻防护网变形对比

Figure 10. Comparisons of instantaneous deformations of barrier

下载: 全尺寸图片幻灯片

图 11 钢丝绳内力时程对比

Figure 11. Comparisons of cable force-time histories

下载: 全尺寸图片幻灯片

图 12 拟分析参数示意图

Figure 12. Diagram of parameters to be analyzed

下载: 全尺寸图片幻灯片

图 13 消能装置规格曲线

Figure 13. Performance curves of energy dissipating devices

下载: 全尺寸图片幻灯片

图 14 不同钢柱倾角下防护网的动态响应

Figure 14. Dynamic responses of barrier in various steel post inclining angle

下载: 全尺寸图片幻灯片

图 15 不同钢柱倾角下防护网的最大变形（侧视图）

Figure 15. Maximum deformation of the barrier under various inclining angles of steel post (side view)

下载: 全尺寸图片幻灯片

图 16 不同钢柱跨距下防护网的动态响应

Figure 16. Dynamic responses of barrier in various steel post spacing

下载: 全尺寸图片幻灯片

图 17 不同钢柱高度下防护网的动态响应

Figure 17. Dynamic responses of barrier in various steel post height

下载: 全尺寸图片幻灯片

图 18 不同消能装置规格下防护网的动态响应

Figure 18. Dynamic responses of barrier in various capacities of energy dissipating device

下载: 全尺寸图片幻灯片

图 19 2种防护网结构布置

Figure 19. Structural layout of two types of barrier designs

下载: 全尺寸图片幻灯片

图 20 欧洲标准^[14]检验结果

Figure 20. Test results based on European standard^[14]

下载: 全尺寸图片幻灯片

图 21 2种设计方案中防护网的动态响应与耗能分布

Figure 21. Dynamic response and energy consumption of two types of barrier designs

下载: 全尺寸图片幻灯片

表 1 防护网主要部件参数^[19]

Table 1. Parameters of main components of barrier^[19]

部件	规格	破断力/kN	消能装置
部件	规格	破断力/kN	F_a～F_s/kN	δ_max/m
网片	R16/3/300
上主支撑绳	2φ22	610	80～100	2.1
下主支撑绳	2φ22	610	80～100	2.1
上次支撑绳	1φ22	305	40～50	2.1
下次支撑绳	1φ22	305	40～50	2.1
侧向支撑绳	1φ22	305	40～50	1.1
上拉锚绳	1φ22	305	80～100	1.1
侧向拉锚绳	1φ22	305
钢柱	HW200×200×8×12

下载: 导出CSV

表 2 防护网各部件材料模型和参数^[19]

Table 2. Material models and corresponding parameters of barrier components^[19]

部件	材料模型	密度/(kg·m^–3)	泊松比	弹性模量/GPa	单元类型
网片	*MAT_PIECEWISE_LINEAR_PLASTICITY	7 850	0.3	200	梁单元
卸扣	*MAT_PLASTIC_KINEMATIC	7 850	0.3	206	梁单元
支撑绳	*MAT_CABLE_DISCRETE_BEAM	7 850	0.3	150	索单元
落石	*MAT_RIGID	2 873	0.3	20	实体单元
消能装置	*MAT_PIECEWISE_LINEAR_PLASTICITY	7 850	0.3	200	梁单元

下载: 导出CSV

表 3 冲击工况

Table 3. Impact scenarios

工况	钢柱角度/(°)	钢柱跨度/m	钢柱高度/m	消能装置规格曲线
1-1	0	9	5.5	0
1-2	10	9	5.5	0
1-3	20	9	5.5	0
1-4	30	9	5.5	0
2-1	10	10	5.5	0
2-2	10	11	5.5	0
3-1	10	9	6.5	0
3-2	10	9	7.5	0
4-1	10	9	5.5	1
4-2	10	9	5.5	2
4-3	10	9	5.5	3
4-4	10	9	5.5	4
4-5	10	9	5.5	5

下载: 导出CSV

表 4 防护网各部件耗能比例

Table 4. Energy consumption ratio of each barrier component

部件	耗能比例系数^[25]	放大系数	设计总耗能能力/kJ
支撑绳上消能装置	0.6	1.5	7 200
拉锚绳上消能装置	0.2	1.5	2 400
其他	0.2	1.5	2 400

下载: 导出CSV

表 5 防护网各部件规格参数

Table 5. Specifications of each barrier component

部件	规格	破断力/kN	消能装置设计值
			F_a～F_s/kN	δ_max/m
			F_a～F_s/kN	方案一	方案二
网片	R19/3/300
上主支撑绳	2φ22	610	250～250	4.00	2.00
下主支撑绳	2φ22	610	250～250	5.00	2.50
上次支撑绳	1φ22	305	150～150	2.50	1.00
下次支撑绳	1φ22	305	150～150	2.50	1.00
辅助支撑绳1和4	2φ22	610	300～300		1.50
辅助支撑绳2和3	2φ22	610	300～300		3.00
侧向支撑绳	1φ22	305	150～150	1.50	1.00
上拉锚绳（内柱）	1φ22	305	150～150	3.00
上拉锚绳（边柱）	1φ22	305	100～100	1.00
上拉锚绳	1φ22	305	100～100		2.00
侧向拉锚绳	1φ22	305

下载: 导出CSV

表 6 防护网检验通过标准和分级标准^[14]

Table 6. Test passing criteria and categorising criteria for barrier^[14]

试验	冲击条件	通过标准	通过后分级标准
SEL-1	落石连续两次冲击网片中心，且两次冲击之间无维护	落石被拦截，连接结构无破坏，残余拦截高度H_R大于标称高度H_N的70%
SEL-2	落石连续两次冲击网片中心，且两次冲击之间无维护	落石被拦截
MEL	落石单次冲击网片中心	落石被拦截	A类：H_R≥50%H_N B类：30%H_N<H_R<50%H_N C类：H_R<30%H_N或上下支撑绳发生断裂

下载: 导出CSV

表 7 检验能级

Table 7. Test energy level

落石试块	冲击能量/kJ	冲击速度/(m·s⁻¹)	质量/kg	名义直径/m
SEL-1试验	2 660	26	7 870	1.567
SEL-2试验	2 660	26	7 870	1.567
MEL试验	8 000	26	23 669	2.266

下载: 导出CSV

表 8 消能装置拉伸变形长度数值模拟结果

Table 8. Simulation results of the elongations of energy dissipating devices

布置位置	F_a～F_s/kN	拉伸变形长度/m
		方案一		方案二
		设计值	模拟值	设计值	模拟值
上主支撑绳	250～250	4.00	3.53	2.00	1.48
下主支撑绳	250～250	5.00	4.58	2.50	2.09
上次支撑绳	150～150	2.50	2.25	1.00	0.83
下次支撑绳	150～150	2.50	2.18	1.00	0.86
辅助支撑绳1和4	300～300			1.50	0.90/1.28
辅助支撑绳2和3	300～300			3.00	2.07/2.83
侧向支撑绳	150～150	1.50	1.18	1.00	0.46
上拉锚绳（内柱）	150～150	3.00	2.84
上拉锚绳（边柱）	100～100	1.00	0.28
上拉锚绳	100～100			2.00	1.87

下载: 导出CSV

参考文献(25)

[1]	SMITH D, DUFFY J D. Field tests and evaluation of rockfall restraining nets: No. CA/TL-90/05 [R]. USA: State of California Department of Transportation, 1990.
[2]	PEILA D, PEIZZA S, SASSUDELLI F. Evaluation of behaviour of rockfall restraining nets by full scale tests [J]. Rock Mechanics and Rock Engineering, 1998, 31(1): 1–24. DOI: 10.1007/s006030050006.
[3]	GRASSL H, VOLKWEIN A, ANDERHEGGEN E, et al. Steel-net rockfall protection-experimental and numerical simulation [C]//Proceedings of the 7th International Conference on Structures Under Shock and Impact. Montreal, Canada: Wit Press, 2002: 143–153.
[4]	BUZZI O, LEONARDUZZI E, KRUMMENACHER B, et al. Performance of high strength rock fall meshes: effect of block size and mesh geometry [J]. Rock Mechanics and Rock Engineering, 2015, 48(3): 1221–1231. DOI: 10.1007/s00603-014-0640-7.
[5]	YU Z X, LIU C, GUO L, et al. Nonlinear numerical modeling of the wire-ring net for flexible barriers [J]. Shock and Vibration, 2019: 3040213. DOI: 10.1155/2019/3040213.
[6]	ZHAO L, YU Z X, LIU Y P, et al. Numerical simulation of responses of flexible rockfall barriers under impact loading at different positions [J]. Journal of Constructional Steel Research, 2020, 167: 105953. DOI: 10.1016/j.jcsr.2020.105953.
[7]	赵雷, 邹定富, 张丽君, 等. 落石被动柔性防护网冲击力学响应的参数化研究 [J]. 振动与冲击, 2023, 42(12): 8–17. DOI: 10.13465/j.cnki.jvs.2023.012.002. ZHAO L, ZOU D F, ZHANG L J, et al. Parametric study on the mechanical response of a flexible rockfall barrier [J]. Vibration and Shock, 2023, 42(12): 8–17. DOI: 10.13465/j.cnki.jvs.2023.012.002.
[8]	KOO R C H, KWAN J S H, LAM C, et al. Dynamic response of flexible rockfall barriers under different loading geometries [J]. Landslides, 2017, 14(3): 905–916. DOI: 10.1007/s10346-016-0772-9.
[9]	QI X, PEI X J, HAN R, et al. Analysis of the effects of a rotating rock on rockfall protection barriers [J]. Geotechnical and Geological Engineering, 2018, 36(5): 3255–3267. DOI: 10.1007/s10706-018-0535-6.
[10]	MOON T, OH J, MUN B. Practical design of rockfall catchfence at urban area from a numerical analysis approach [J]. Engineering Geology, 2014, 172: 41–56. DOI: 10.1016/j.enggeo.2014.01.004.
[11]	YU Z X, LUO L, LIU C, et al. Dynamic response of flexible rockfall barriers with different block shapes [J]. Landslides, 2021, 18(7): 2621–2637. DOI: 10.1007/s10346-021-01658-w.
[12]	GERBER W. Guideline for the approval of rockfall protection kits: environment in practice [R]. Bern, Switzerland: Swiss Agency for the Environment, Forest and Landscape (SAEFL), Swiss Federal Research Institute (WSL), 2001.
[13]	HIGGINS J D. Recommended procedure for the testing of rock-fall barriers: NCHRP Project 20–07, Task 138 [R]. Washington, USA: National Cooperative Highway Research Program, Transportation Research Board, 2003.
[14]	ETOA. Falling rock protection kits: EAD 340059-00-0106 [S]. Brussels: European Organization for Technical Approvals, 2018.
[15]	国家铁路局. 铁路边坡柔性被动防护产品落石冲击试验方法与评价: TB/T 3449—2016 [S]. 北京: 中国铁道出版社, 2016.
[16]	中华人民共和国交通运输部. 边坡柔性防护网系统: JT/T 1328—2020 [S]. 北京: 人民交通出版社, 2020.
[17]	李自名. 柔性拦截网顶破力学行为研究 [D]. 成都: 西南交通大学, 2019: 19–29.
[18]	郭立平. 柔性防护工程环连网静动力行为与破坏力学模型 [D]. 成都: 西南交通大学, 2023: 32–41.
[19]	YU Z X, QIAO Y K, ZHAO L, et al. A simple analytical method for evaluation of flexible rockfall barrier part 2: application and full-scale test [J]. Advanced Steel Construction, 2017, 14(2): 142–165. DOI: 10.18057/IJASC.2018.14.2.2.
[20]	齐欣. 柔性被动拦截网结构力学性能研究 [D]. 西南交通大学, 2014: 126–131.
[21]	罗祥, 石少卿, 汪敏. 边坡柔性防护网中RECCO圆环力学性能研究 [J]. 路基工程, 2010(6): 45–47. DOI: 10.3969/j.issn.1003-8825.2010.06.016. LUO X, SHI S Q, WANG M. Study on mechanic properties of RECCO ring in slope flexible protecting fence [J]. Subgrade Engineering, 2010(6): 45–47. DOI: 10.3969/j.issn.1003-8825.2010.06.016.
[22]	ESCALLóN J P, WENDELER C, CHATZI E N, et al. Parameter identification of rockfall protection barrier components through an inverse formulation [J]. Engineering Structures, 2014, 77: 1–16. DOI: 10.1016/j.engstruct.2014.07.019.
[23]	BOYCE B L, DILMORE M F. The dynamic tensile behavior of tough, ultrahigh-strength steels at strain-rates from 0.000 2 s^–1 to 200 s^–1 [J]. International Journal of Impact Engineering, 2009, 36(2): 263–271. DOI: 10.1016/j.ijimpeng.2007.11.006.
[24]	LSTC. LS-DYNA keyword userʼs manual volume Ⅰ [M]. California: Livermore Software Technology Corporation (LSTC), 2013: 2068–2073.
[25]	四川省质量技术监督局. 公路被动柔性防护网技术规程: DB51/T 2432—2017 [S]. 北京: 人民交通出版社, 2017.