碎石锚固中压力拱形成与锚杆作用分析
Analysis of pressure arch formation and rockbolt function in gravel bolting
-
摘要: 碎石锚固试验被用于证实锚固破碎岩体中存在压力拱，但压力拱的概念较为抽象，难以理解和应用。为研究锚固破碎岩体中压力拱的形成机制与锚杆的作用，克服颗粒锚杆批量生成与预紧难题，利用三维颗粒流程序（PFC3D）开发碎石锚固试验的数值模拟方法，开展系列碎石锚固数值试验，直观展示压力拱的形成，揭示压力拱的形成机制与成因，分析并验证锚杆在压力拱形成中的具体作用。在此基础上，提出极破碎岩体锚杆加固的建议。研究结果表明：① 锚杆加固碎石体内会形成拱形承载结构压力拱，压力拱由碎石咬合而成，碎石体全部质量由压力拱承载，压力拱的稳定依靠拱下碎石支撑。② 压力拱形成于碎石在锚杆作用下的自适应运动过程。移除碎石箱底板后，底部碎石向下运动，导致上部碎石重力向周边转移，在周边碎石形成拱腿，拱顶部位碎石在侧向约束作用下彼此咬合形成拱顶，最终以底托板为基础形成压力拱。③ 压力拱的形成和稳定需满足4个条件：强力的底部基础、足够的侧向约束、适当的碎石厚度和平衡的拱下碎石。④ 锚杆在压力拱形成和稳定中发挥侧向约束作用、支撑作用和护表作用。在成拱过程中，锚杆通过预紧提供侧向约束力，使碎石具有足以成拱的咬合能力。在压力拱形成后，锚杆通过对拱下碎石提供支撑和护表使其平衡，维护压力拱的稳定。锚杆预紧有助于增强侧向约束作用和支撑作用。⑤ 大范围极破碎岩体加固应围绕压力拱的形成，充分发挥锚杆的侧向约束、支撑和护表作用，包括提高锚杆预紧力、增大锚杆杆体粗糙度、减小锚杆间距、增大托盘尺寸等。Abstract: The gravel bolting tests has been used to verify the existence of pressure arch in bolted fractured rock,however,the pressure arch is difficult to understand and used due to the abstract concept.In order to study the formation mechanism of pressure arch and the functions of rockbolts in bolted fractured rock,the numerical simulation of gravel bolting tests by using the Particle Flow Code in 3 Dimensions(PFC3D)was achieved through developing the methods of batch generation and pretension for rockbolts simulated by particles.A series of gravel bolting tests were performed to visualize the pressure arch and reveal its formation mechanism and causes.The functions of rockbolts in gravel bolting tests were analyzed and verified.Base on the above,some suggestions were made for bolting in extremely fractured rock.The results show that:① A pressure arch can be formed in bolted gravel pack,which is an arched load bearing structure made of interlocked gravel particles.The load of the whole gravel pack is carried by the pressure arch,and the stability of pressure arch depend on the support from the gravel below the pressure arch.② Pressure arch is formed in the adaptive motion process of gravel particles under bolting.After the removal of bottom plate of gravel box,the gravity of upper gravel shifts to the periphery due to the downward movement of bottom gravel,forming arch legs in surrounding gravel.The gravel particles at the top of the arch interlock each other to form the vault,resulting in a formation of pressure arch based on the backing boards.③ The formation of a pressure arch needs to meet four conditions:a strong bottom base,a sufficient lateral constraint,a proper thickness of gravel pack and some balanced gravel particles below the arch.④ Lateral restraint,support and surface retention are exerted by rockbolts to gravel particles in gravel bolting tests.In the formation of a pressure arch,the rockbolts are pretensioned to generate lateral restraint on the gravel pack,so that the gravel particles have sufficient interlocking capacity for arching.After the formation,the rockbolts can maintain the stability of pressure arch by providing support and surface retention for gravel particles below the pressure arch.The pretention of rockbolts helps to increase the lateral restraint and supporting effect.⑤ The lateral restraint,supporting and surface retaining effects of rockbolts should be fully developed to build up a pressure arch in a large scale extremely fractured rock,including increasing pretension force,increasing the roughness of the rockbolt bodies,reducing the spacing between rockbolts,enlarging the size of plates and installing mesh,etc.
-
Keywords:
- gravels /
- rockbolts reinforcement test /
- pressure arch /
- rockbolts function /
- PFC3D
-
-
期刊类型引用(19)
1. 马凯蒙，张俊儒，颜志坚，汪波. 隧道压力(承载)拱研究现状与展望. 地下空间与工程学报. 2025(02): 551-562 . 
百度学术
2. 杨扬，孙凯，于振亚. 回采巷道锚杆索支护优化设计与应用. 山东煤炭科技. 2024(02): 6-10+15 . 百度学术
3. 王卫军，范磊，赵志强，韩森. 基于塑性区控制的巷道围岩支护理论与技术研究进展. 煤炭学报. 2024(01): 320-336 . 本站查看
4. 王立华，刘源，孙捷城，李洁，吕显州，王渭明. 基于压力拱发展规律的隧道初次支护时机研究. 广西大学学报(自然科学版). 2024(01): 37-48 . 百度学术
5. 原贵阳，高富强，王涛，李建忠，王晓卿. 锚网-围岩接触面注浆充填预应力施加技术. 煤炭学报. 2024(05): 2222-2230 . 本站查看
6. 张文龙，龙思晨，孙思晋，梁子晨. 层理劣化影响下破碎顶板巷道变形机理及控制研究. 煤炭工程. 2024(06): 55-60 . 百度学术
7. 袁刚，徐金峰，李守仁，石州，严绍明. 强风化花岗混合岩上硬下软地层公路隧道施工优化. 公路交通科技. 2024(07): 153-162 . 百度学术
8. 王方田，江振鹏，刘超，何东升，郝文华，屈鸿飞. 深井综采面动压区沿空留巷围岩变形机理及锚索强化支护技术. 采矿与安全工程学报. 2024(06): 1103-1115 . 百度学术
9. 赵振飞，高雁，刘文学. 近距离下层煤回采巷道变形机理及支护研究. 煤炭技术. 2024(12): 62-67 . 百度学术
10. 高鹏，赵志宁，杜厚霖，潘卫东，查大顺. 端头放煤区域巷道围岩稳定性的数值模拟研究. 矿业科学学报. 2024(06): 884-896 . 百度学术
11. 王晓卿. 锚杆预紧对破碎岩体锚固与承载特性的影响. 煤炭学报. 2024(S2): 606-615 . 本站查看
12. 孙振宇，皇甫楠琦，张顶立，李沐阳，王嘉琛. 大跨度隧道预应力锚固体系协同承载的压力拱效应. 铁道标准设计. 2023(01): 10-16+24 . 百度学术
13. 王朋飞，常通，卢俊宇，薛佩峰，张海龙，高翔，曲越，刘佳男. 再论负煤柱巷顶沿空掘巷合理位置及其围岩主动控制原理. 煤炭学报. 2023(02): 593-608 . 本站查看
14. 李亮，何富连，许旭辉，秦宾宾，吕凯，翟文立，宋佳宇. 近距离煤层应力拱形态与支承压力分布演化研究. 采矿与安全工程学报. 2023(02): 295-303 . 百度学术
15. 石垚. 预应力锚杆支护应力场叠加效应试验研究. 能源与环保. 2023(11): 51-60 . 百度学术
16. 石垚. 锚杆不同护表构件支护应力场分布规律试验研究. 煤炭工程. 2023(12): 134-140 . 百度学术
17. 孟波，靖洪文，吴疆宇，李晓昭，董津源，尹乾. 破碎岩石锚固结构承载力学特性模型试验研究. 岩石力学与工程学报. 2023(12): 3020-3030 . 百度学术
18. 李建忠，高富强，娄金福，原贵阳. 破碎岩体锚固及承载失稳机制研究. 采矿与安全工程学报. 2022(06): 1125-1134 . 百度学术
19. 张坤，李玉霞，钟东虎，孟祥军，黄庆学，徐亚军，陈洪月，马英，张德生，黄梁松，苏金鹏. 超前液压支架群组–锚固耦合支护力学特性研究及实验验证. 岩石力学与工程学报. 2021(07): 1428-1443 . 百度学术
其他类型引用(22)
下载:
图(14)
计量
- 文章访问数: 869
- HTML全文浏览量: 16
- PDF下载量: 1116
- 被引次数: 41
