Anti-detonation property of reinforcement rock
-
摘要: 为进一步提升岩体的抗爆炸性能,采用相似模型实验和数值模拟的方法对采用交叉锚索进行加固的围岩进行了抗爆性能分析,对比分析了加固前后岩体的爆炸压力分布规律、应变分布规律、爆腔大小以及锚索参数对加固效果的影响。研究结果表明:无论岩体是否加固,爆心附近岩体内爆炸压力峰值、径向应变峰值、环向应变峰值与比例距离均呈负幂指数衰减,在相同的爆炸药量作用下,随着距爆点距离的增大,压力、应变峰值迅速减小;在集团装药条件下,岩体内的爆腔不呈球形而呈上细下粗的花瓶形,且无加固岩体的爆腔高度较大;交叉锚索角度变化对介质压缩半径的影响较小;随着交叉锚索密度的增大,加固介质中自由场压缩波峰值降低约20%~35%左右,介质的破坏半径小约30%左右。该研究结果可为地下防护工程设计和围岩加固提供参考。Abstract: To improve the anti-detonation property of surrounding rock, the surrounding rock reninforced by crossing cable method was proposed, and the effects of the method were analyzed by anology experiments and numerical simulation. The d pressure and strain distributions under detonation, explosion cavity dimensions and reinforcing cable parameters on strengthening effects were investigated. The results indicate that the detonation pressure peak value near the detonation center, radial strain peak value and circumferential strain peak value are all negative exponential decay with the proportional distance, no matter the rock is strengthened or not. Under the focus point explosion, the pressure and peak strain rapidly decrease with the distance apart from the detonation point. Under the concentrated charging case, the explosion cavity displays as a vase with the thin head part and fat bottom part. The explosion cavity of the magmatic body without strengthening is comparatively large. The influences of reinforced crossing cable angle on medium compression radius is limited. With the increase of the density of the reinforced crossing cable, the peak value of the compression wave in the strengthened medium decreases about 20%-35% and the destruction radius decreases about 30%. The results of this paper can provide references to the underground protective engineering design and enclosing rock strengthening.
-
Key words:
- anti-detonation property /
- model test /
- reinforcement /
- anchor cable /
- explosion cavity
-
表 1 原岩与选定模拟材料物理力学参数
Table 1. Mechanics parameters of the rock and selected material
围岩级别 Rc/MPa Rt/MPa C/MPa φ/(°) Em/GPa μ ρ/(kg·m−3) 原岩(Ⅲ) 30 0.83~1.4 0.7~1.5 35~45 6.0~20 0.20~0.25 2 500 选定的模型材料 2.56 0.43 1.5 41 5.2 0.15 1 820 表 2 钢绞线与选定铝绞线力学参数
Table 2. The mechanics parameters of cable and selected aluminium stranded wire
锚索类型 E/GPa Rt/MPa 规格 R/mm A/mm2 钢绞线(原型) 196 1 860 3束7×$\varnothing $5 mm 23.05 417 铝绞线(模型) 62.6 170 3×$\varnothing $1.5 mm 2.6 5.3 表 3 数值模型参数
Table 3. Parameters of numerical model
角度/(°) ρ/(kg·m−3) E/GPa μ Rc/MPa Rt/MPa C/MPa φ/(°) 无加固 1 800 0.386 0.25 3 0.267 0.6 36 45 2 000 0.735 0.25 3 0.497 0.8 41 30 2 000 0.70 0.25 3 0.803 0.85 39 60 2 000 0.78 0.25 3 0.320 0.75 45 注:角度指锚索与水平线之间角度。 表 4 数值模拟计算方案
Table 4. The proposal of the numerical simulations
编号 ρm E/GPa φ/(°) C/MPa Rt/MPa Cm/(°) Ry/mm M1 0.1 m×0.1 m 0.700 39 0.85 0.803 30 241 M2 0.1 m×0.1 m 0.735 41 0.80 0.497 45 251 M3 0.1 m×0.1 m 0.780 45 0.75 0.320 60 258 M4 0.07 m×0.07 m 0.700 41 0.80 0.75 45 222 M5 0.15 m×0.15 m 0.780 41 0.80 0.35 45 278 -
[1] ANDERS A. Laboratory testing of a new type of energy absorbing rock bolt [J]. Tunnelling and Underground Space Technology, 2005, 20(4): 291–300. DOI: 10.1016/j.tust.2004.12.001. [2] TANNANT D D, BRUMMER R K. Rock bolt behavior under dynamic loading field tests and modeling [J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, 1995, 32(6): 537–550. DOI: 10.1016/0148-9062(95)00024-B. [3] 方从严, 卓家寿. 锚杆加固机制的试验研究现状 [J]. 河海大学学报: 自然科学版, 2005, 33(6): 696–700. DOI: 10.3321/j.issn:1000-1980.2005.06.021.FANG Congyan, ZHUO Jiashou. Experimental study actuality of rock bolts reinforcement mechanism [J]. Journal of Hohai University: Natural Science, 2005, 33(6): 696–700. DOI: 10.3321/j.issn:1000-1980.2005.06.021. [4] ORTLEPP W D, STACEY T R. Performance of tunnel support under large deformation static and dynamic loading [J]. Tunnelling and Underground Space Technology, 1998, 13(1): 15–21. DOI: 10.1016/S0886-7798(98)00022-4. [5] 杨自友, 顾金才, 陈安敏, 等. 爆炸波作用下锚杆间距对围岩加固效果影响的模型试验研究 [J]. 岩石力学与工程学报, 2008, 27(4): 757–764. DOI: 10.3321/j.issn:1000-6915.2008.04.015.YANG Ziyong, GU Jincai, CHEN Anmin, et al. Model experiment study on influences of reinforcement on intervals of rock bolts in surrounding rock under explosive waves [J]. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(4): 757–764. DOI: 10.3321/j.issn:1000-6915.2008.04.015. [6] 陈剑杰, 孙钧, 林俊德, 等. 强爆炸应力波作用下岩石地下洞室的破坏现象学 [J]. 解放军理工大学学报, 2007, 8(6): 582–588. DOI: 10.3969/j.issn.1009-3443.2007.06.005.CHEN Jianjie, SUN Jun, LIN Junde, et al. Failure of rock openings under intensive explosion stress wave [J]. Journal of PLA University of Science and Technology, 2007, 8(6): 582–588. DOI: 10.3969/j.issn.1009-3443.2007.06.005. [7] 杨苏杭, 梁斌, 顾金才, 等. 锚固洞室抗爆模型试验锚索预应力变化特性研究 [J]. 岩石力学与工程学报, 2006, 25(增2): 3749–3756. DOI: 10.3321/j.issn:1000-6915.2006.z2.065.YANG Suhang, LIANG Bin, GU Jincai, et al. Research on characteristics of prestress change of anchorage cable in anti-explosion model test of anchored cavern [J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25(s2): 3749–3756. DOI: 10.3321/j.issn:1000-6915.2006.z2.065. [8] 王光勇, 顾金才, 陈安敏, 等. 顶爆作用下锚杆破坏形式及破坏机制模型试验研究 [J]. 岩石力学与工程学报, 2012, 31(1): 27–31. DOI: 10.3969/j.issn.000-6915.2012.01.004.WANG Guangyong, GU Jincai, CHEN Anmin, et al. Model test research on failure forms and failure mechanism of anchor bolts under top explosion [J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(1): 27–31. DOI: 10.3969/j.issn.000-6915.2012.01.004. [9] 徐景茂, 顾金才, 陈安敏, 等. 拱脚局部加长锚杆锚固洞室抗爆模型试验研究 [J]. 岩石力学与工程学报, 2012, 31(11): 2182–2186. DOI: 10.3969/j.issn.1000-6915.2012.11.005.XU Jingmao, GU Jincai, CHEN Anmin, et al. Model test study of anti-explosion capacity of anchored tunnel with local lengthening anchors in arch springing [J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(11): 2182–2186. DOI: 10.3969/j.issn.1000-6915.2012.11.005. [10] 徐干成, 顾金才, 袁伟泽, 等. 洞室围岩交叉锚固结构抗爆性能模型试验研究 [J]. 地下空间与工程学报, 2014, 10(5): 1078–1085.XU Gancheng, GU Jincai, YUAN Weize, et al. Model test study on explosive resistance of intercross bolted rock mass structure in underground space [J]. Chinese Journal of underground space and Engineering, 2014, 10(5): 1078–1085. [11] 徐干成, 顾金才, 张向阳, 等. 地下洞库围岩外加固抗炸弹侵彻性能研究 [J]. 岩石力学与工程学报, 2012, 31(10): 2064–2070. DOI: 10.3969/j.issn.1000-6915.2012.10.011.XU Gancheng, GU Jincai, ZHANG Xiangyang, et al. Penetration resistivity research on anchored cavern surface rock [J]. Chinese Journal of Rock Mechanics and Engineering, 2012, 31(10): 2064–2070. DOI: 10.3969/j.issn.1000-6915.2012.10.011. [12] 徐干成, 袁伟泽, 顾金才, 等. 地下洞库围岩外加固抗炸弹爆炸性能研究 [J]. 岩石力学与工程学报, 2015, 34(9): 1767–1776. DOI: 10.13722/j.cnki.jrme.2014.1676.XU Gancheng, YUAN Weize, GU Jincai, et al. Explosive resistivity research on anchored cavern surface rock [J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(9): 1767–1776. DOI: 10.13722/j.cnki.jrme.2014.1676. [13] 徐干成, 袁伟泽, 顾金才, 等. 围岩外加固抗爆炸成坑试验研究 [J]. 岩石力学与工程学报, 2017, 36(10): 2441–2448. DOI: 10.13722/j.cnki.jrme.2016.1646.XU Gancheng, YUAN Weize, GU Jincai, et al. Modeling test on explosion cavity to study anchored surface rock around cavern [J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(10): 2441–2448. DOI: 10.13722/j.cnki.jrme.2016.1646.