输电线路单群锚基础抗拔特征差异的现场足尺试验

张文翔; 崔强; 邱昊茨; 陆洲; 奚邦禄; 张振华

doi:10.19509/j.cnki.dzkq.tb20240221

输电线路单群锚基础抗拔特征差异的现场足尺试验

doi: 10.19509/j.cnki.dzkq.tb20240221

张文翔^1,,
崔强^2, ,,
邱昊茨³,
陆洲¹,
奚邦禄⁴,
张振华⁴

1.
中国电建集团福建省电力勘测设计院有限公司, 福建福州 350003
2.
中国电力科学研究院有限公司, 北京 102401
3.
国网泉州供电公司, 福建泉州 362000
4.
合肥工业大学土木与水利工程学院, 合肥 230009

基金项目:

国网福建省电力有限公司科技项目-适用于福建地区输电线路锚杆复合基础研究 521330210078

详细信息

作者简介:
张文翔, E-mail: 495529242@qq.com

通讯作者:
崔强, E-mail: everjsl@126.com

中图分类号: TM75;TU470
计量
- 文章访问数: 88
- PDF下载量: 21
- 被引次数: 0
出版历程
- 收稿日期: 2024-05-04
- 录用日期: 2024-08-10
- 修回日期: 2024-08-01

On-site full-scale test research for difference of anti-pull bearing characteristics between single anchor and group anchors foundation of transmission lines

1.
Power China Fujian Electric Power Engineering Co., Ltd., Fuzhou Fujian 350003, China
2.
China Electric Power Research Institute, Beijing 102401, China
3.
State Grid Fujian Quanzhou Electric Power Supply Company, Quanzhou Fujian 362000, China
4.
College of Civil Engineering, Hefei University of Technology, Hefei 230009, China

More Information

Author Bio:
ZHANG Wenxiang, E-mail: 495529242@qq.com

Corresponding author: CUI Qiang, E-mail: everjsl@126.com

摘要

摘要:
为研究输电线路单锚与群锚基础抗拔承载特征差异, 采用理论分析和现场试验相结合的研究方法, 首先根据结构特点, 从受力与变形2方面分析了单锚与群锚的承载机制; 然后以输电线路基础工程中常用的全长黏结型锚杆为研究对象, 选取位于福建泉州地区的花岗岩地基作为试验场地, 分别开展了3组单锚、4组群锚的现场足尺拉拔试验, 采用位移传感器测试基础与地基变形、采用光频域反射光纤传感技术测试锚杆应变, 分析得到试验基础的荷载位移曲线以及锚杆界面内力分布; 最后对受力过程中2类锚杆基础的变形破坏机制进行对比分析。结果表明: 单锚与群锚荷载位移曲线特征存在差异, 群锚反映出的塑性变形特征较单锚明显; 加载前半段, 锚杆体系位移以锚筋拉伸为主, 加载后半段, 以锚岩界面滑移为主; 锚杆截面轴向应力沿深度方向逐渐减小, 且最终在2~3 m深度处趋于0;拉拔荷载作用下的单锚破坏模式与基岩饱和单轴抗压强度有关, 而群锚的破坏模式与组成的单锚数量有关; 工程中建议以群锚基础试验获得锚岩界面黏结强度为设计依据。研究成果可为输电线路岩石锚杆基础的选型与设计提供参考。
- 输电线路 /
- 锚杆基础 /
- 现场足尺试验 /
- 分布式光纤 /
- 锚岩黏结强度 /
- 拉拔试验
Abstract: Objective
To investigate the differences in anti-pull bearing characteristics between single anchor and group anchors foundations of transmission lines,
Methods
this study employs a combination of theoretical analysis and field experiments. First, based on the structural characteristics, the bearing mechanisms of singleand group anchors were analyzed in terms of force and deformation. The full-length bonded anchors, commonly used in transmission line projects, were selected as the research object, with the granite ground in Quanzhou selected as the test site. On-site full-scale tests were conducted on three single anchors and four group anchors. Displacement sensors were used to monitor foundation and ground deformation, while optical frequency domain reflectometry (OFDR) recorded the strain in the anchor rods. The load-displacement curve of the test foundation and the internal force distribution along the anchor interface were obtained. Finally, a comparative analysis of the deformation and failure mechanisms for both anchor types was performed.
Results
The results show that the load-displacement curve of a single anchor differs from that of group anchors, with plastic deformation being more pronounced in group anchors. In the initial stages of testing, anchor system displacement is primarily governed by the tension in the anchor bars, whereas at the end of the test, displacement is more influenced by slippage at the anchor-rock interface. The axial tension stress of the anchor rod decreases gradually with depth, reaching near-zero at depths of 2 to 3 m. The failure mode of a single anchor under tensile load is related to the saturated uniaxial compressive strength of rock, while the failure mode for group anchors is influenced by the number of single anchor. It is recommended that group anchors foundation tests be used to determine the bond strength at the anchor interface for design purposes in engineering applications.
Conclusion
The research findings can provide references for the selection and design of rock anchor foundations for transmission lines.
- transmission line /
- anchor foundation /
- on-site full-scale test /
- distributed optical fiber /
- anchor rock bond strength /
- bearing test
注释:

所有作者声明不存在利益冲突。

HTML全文

图 1 现场岩土体芯样

Figure 1. On-site geotechnical core samples

下载: 全尺寸图片幻灯片

图 2 试验基础结构示意图

a.单锚; b.群锚; c. 群锚平面布置图; d.锚孔直径；h.锚孔深度；h₀.锚筋自由段长度；下同

Figure 2. Schematic diagram of test foundations

下载: 全尺寸图片幻灯片

图 3 试验基础现场制作工序

Figure 3. On-site construction process of test foundation

下载: 全尺寸图片幻灯片

图 4 试验加载装置

Figure 4. Test loading device

下载: 全尺寸图片幻灯片

图 5 测试元件布置图

S₁~S₆.位移传感器符号；下同

Figure 5. Layout of testing components

下载: 全尺寸图片幻灯片

图 6 单锚与群锚荷载-位移曲线对比分析

Figure 6. Comparative analysis of load-displacement curves between single anchor and group anchors

下载: 全尺寸图片幻灯片

图 7 不同位置处位移分布曲线(Q为上拔荷载, Q_de为破坏荷载，Q=90%Q_de)

Figure 7. Displacement distribution curves at different locations

下载: 全尺寸图片幻灯片

图 8 锚杆轴向应力沿深度分布曲线

Figure 8. Axial stress distribution curve of anchor rod along depth

下载: 全尺寸图片幻灯片

图 9 锚杆基础拉拔试验4种常见的破坏模式

Figure 9. Four common failure modes in anchor foundation pullout tests

下载: 全尺寸图片幻灯片

图 10 地基破坏时地表形成的贯通裂缝

Figure 10. Surface cracks formed during foundation failure

下载: 全尺寸图片幻灯片

图 11 锚岩界面黏结强度随深度分布曲线

Figure 11. Distribution curve of anchor-rock interface bond strength with depth

下载: 全尺寸图片幻灯片

表 1 现场岩体物理力学参数(2 m深度处)

Table 1. Physical and mechanical parameters of on-site rockmass

指标	试验值
密度/(g·m^-3)	2.66
含水率/%	13
劈裂抗拉强度/MPa	7.9
单轴抗压强度/MPa	47
饱和单轴抗压强度/MPa	35
弹性模量/GPa	9.04
黏聚力/MPa	11.3
内摩擦角/(°)	50

下载: 导出CSV

表 2 7个试验基础尺寸参数

Table 2. Geometric size parameters of 7 test foundations

类型	编号	d₀/m	d/m	h/m	h₀/ m	锚杆数量/根
单锚	DM1	0.032	0.13	4	0.5	1
	DM2	0.032	0.13	4	0.5	1
	DM3	0.032	0.13	4	0.5	1
群锚	QM4-1	0.032	0.13	4	0.5	4
	QM4-2	0.032	0.13	4	0.5	4
	QM6-1	0.032	0.13	4	0.5	6
	QM6-2	0.032	0.13	4	0.5	6
注：d₀为锚筋直径；d为锚孔直径；h为锚孔深度；h₀为锚筋自由段长度。锚筋与锚孔底部预留0.15 m保护层

下载: 导出CSV

表 3 不同加载阶段锚筋拉长量Δs₁和锚筋与界面滑移量Δs₂占比

Table 3. Proportion of anchor elongation and interface slippage at different loading stages

编号	Q=30%Q_de		Q=60%Q_de		Q=90%Q_de
编号	M_Δs₁	M_Δs₂	M_Δs₁	M_Δs₂	M_Δs₁	M_Δs₂
DM1	69%	31%	65%	35%	28%	72%
DM2	65%	35%	61%	39%	23%	77%
DM3	68%	32%	67%	33%	34%	66%
QM4-1	57%	43%	60%	40%	28%	72%
QM6-2	59%	41%	57%	43%	34%	66%
注: M_Δs₁、M_Δs₂分别为Δs₁、Δs₂占总变形量的百分比; Q为上拔荷载；Q_de为破坏荷载；下同

下载: 导出CSV

表 4 5根试验锚杆轴向应力零值点深度

Table 4. Depth of zero axial stress point of 5 test anchor rods

编号	距地面深度/m
编号	首级荷载	Q=30%Q_de	Q=60%Q_de	屈服前一级荷载
DM1	2.4	2.5	2.7	2.8
DM2	2.1	2.3	2.5	2.6
DM3	1.5	1.6	1.8	2.0
QM4-1	2.1	2.3	2.5	2.5
QM6-1	2.6	2.8	2.8	—

下载: 导出CSV

表 5 4组锚杆拉拔试验结果对比

Table 5. Comparison of four sets of anchor pull-out test results

基岩类型	饱和单轴抗压强度/MPa	破坏模式
阳江灰岩^[29]	97.57	锚筋拉断
宜昌灰岩^[30]	61.01	锚筋拉断
宣城灰岩^[31]	42.7	锚筋拉断
泉州花岗岩	35	包裹体与岩体界面破坏
注：锚筋均采用32，HRB400材质螺纹钢，锚孔直径为130 mm，包裹体为C30细石混凝土，锚杆黏结长度4 m

下载: 导出CSV

表 6 各试验基础极限抗拔承载力及极限位移

Table 6. Ultimate uplift bearing capacity and ultimate displacement of each test foundation

编号	R_u/kN	s_u/mm	(R_u/Q_de)/%	失效准则
DM1	320	0.65	80	①
DM2	330	3.34	70	①+②
DM3	280	2.53	70	①
QM4-1	1 440	3.13	70	①
QM4-2	1 440	2.36	70	①
QM6-1	1 920	2.87	60	①
QM6-2	1 920	4.54	60	①
注：①锚筋屈服时前一级荷载；②荷载位移曲线陡变起始点对应荷载^[5]; R_u.极限承载力; s_u.允许位移

下载: 导出CSV

表 7 锚岩界面黏结强度规范推荐值^[5]

Table 7. Recommended values for the bond strength of the anchor-rock interfaces

基岩类型	锚岩黏结强度标准值/kPa
极软岩	[150, 250)
软岩	[250, 600)
较软岩	[600, 900)
较硬岩	[900, 1 500)
坚硬岩	[1 500, 2 500]
注：包裹体为细石混凝土或水泥砂浆

下载: 导出CSV

表 8 锚岩界面黏结强度推算值

Table 8. Calculated values of anchor-rock interface bond strength

编号	深度/m	黏结强度τ/kPa
编号	深度/m	推算值	均值
DM1	0~2.8	1 510
DM2	0~2.6	1 674	1 902
DM3	0~2.0	2 522
QM4-1	0~2.6	1 186	1 186

下载: 导出CSV

参考文献(31)

[1]	邬礼扬, 殷坤龙, 曾韬睿, 等. 不同栅格尺寸下输电线路地质灾害易发性评价[J]. 地质科技通报, 2024, 43(1): 241-252. doi: 10.19509/j.cnki.dzkq.tb20220307 WU L Y, YIN K L, ZENG T R, et al. Evaluation of geological disaster susceptibility of transmission lines under different grid resolutions[J]. Bulletin of Geological Science and Technology, 2024, 43(1): 241-252. (in Chinese with English abstract) doi: 10.19509/j.cnki.dzkq.tb20220307
[2]	李思德, 李远耀, 殷坤龙, 等. 基于物理模型试验的杆塔基础滑坡防护措施效果研究[J]. 地质科技通报, 2022, 41(2): 209-218. doi: 10.19509/j.cnki.dzkq.2022.0044 LI S D, LI Y Y, YIN K L, et al. Study on the effect of tower foundation landslide protection measures based on a physical model test[J]. Bulletin of Geological Science and Technology, 2022, 41(2): 209-218. (in Chinese with English abstract) doi: 10.19509/j.cnki.dzkq.2022.0044
[3]	朴昇昊, 张伟丽, 王永一, 等. 冻融循环对GFRP锚杆锚固性能影响的试验研究[J]. 地质科技通报, 2022, 41(6): 301-307. doi: 10.19509/j.cnki.dzkq.2021.0055 PIAO S H, ZHANG W L, WANG Y Y, et al. Experimental study on the influence of freeze-thaw cycles on the anchoring performance of GFRP anchor[J]. Bulletin of Geological Science and Technology, 2022, 41(6): 301-307. (in Chinese with English abstract) doi: 10.19509/j.cnki.dzkq.2021.0055
[4]	鲁先龙, 崔强. 架空输电线路基础设计[M]. 北京: 中国电力出版社, 2021. LU X L, CUI Q. Design of foundation for overhead transmission line[M]. Beijing: China Eclectic Power Press, 2021. (in Chinese)
[5]	中华人民共和国国家能源局. 架空输电线路基础设计规程: DL/T 5219-2023[S]. 北京: 中国计划出版社, 2023. National Energy Bureau of the People's Republic of China. Specification for design of foundation of overhead transmission line: DL/T 5219-2023[S]. Beijing: China Planning Press, 2023. (in Chinese)
[6]	ITO F, NAKAHARA F, KAWANO R, et al. Visualization of failure in a pull-out test of cable bolts using X-ray CT[J]. Construction and Building Materials, 2001, 15(5/6): 263-270.
[7]	KILIC A, YASAR E, CELIK A G. Effect of grout properties on the pull-out load capacityof fully grouted rock bolt[J]. Tunnelling and Underground Space Technology, 2002, 17(4): 355-362. doi: 10.1016/S0886-7798(02)00038-X
[8]	KIM D H, LEE S R. Uplift capacity of fixed shallow anchors subjected to vertical loading in rock[J]. International Journal of Offshore and Polar Engineering, 2005, 15(4): 312-320.
[9]	MA S Q, NEMCIK J, AZIZ N. An analytical model of fully grouted rock bolts subjected to tensile load[J]. Construction and Building Materials, 2013, 49: 519-526. doi: 10.1016/j.conbuildmat.2013.08.084
[10]	PARK J, QIU T, KIM Y. Field and laboratory investigation of pullout resistance of steel anchors in rock[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2013, 139(12): 2219-2224. doi: 10.1061/(ASCE)GT.1943-5606.0000953
[11]	CHEN Y. Experimental study and stress analysis of rock bolt anchorage performance[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2014, 6(5): 428-437. doi: 10.1016/j.jrmge.2014.06.002
[12]	GHADIMI M, SHAHRIAR K, JALALIFAR H. Analysis profile of the fully grouted rock bolt in jointed rock using analytical and numerical methods[J]. International Journal of Mining Science and Technology, 2014, 24(5): 609-615. doi: 10.1016/j.ijmst.2014.07.009
[13]	HE L, AN X M, ZHAO Z Y. Fully grouted rock bolts: An analytical investigation[J]. Rock Mechanics and Rock Engineering, 2015, 48(3): 1181-1196. doi: 10.1007/s00603-014-0610-0
[14]	孙益振, 郑卫锋, 范志强. 输电线路节理化岩体注浆锚杆基础抗拔力模型试验研究[J]. 岩土力学, 2012, 33(1): 78-82. SUN Y Z, ZHENG W F, FAN Z Q. Tension model test research on grouted bolts foundation in jointed rock masses for transmission lines[J]. Rock and Soil Mechanics, 2012, 33(1): 78-82. (in Chinese with English abstract)
[15]	曾华明, 李祺, 岳向红. 张拉荷载下砂浆锚固岩石锚杆的力学分析[J]. 岩石力学与工程学报, 2006, 25(增刊2): 3982-3986. ZENG H M, LI Q, YUE X H. Analysis of mechanical behavior of fully grouted rock bolt under tensile load[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25(S2): 3982-3986. (in Chinese with English abstract)
[16]	孙长帅, 杨海巍, 徐光黎. 岩石锚杆基础抗拔承载力计算方法探究[J]. 岩土力学, 2009, 30(增刊1): 75-78. SUN C S, YANG H W, XU G L. Researches on pull-out capacity calculating method of rock bolt foundation[J]. Rock and Soil Mechanics, 2009, 30(S1): 75-78. (in Chinese with English abstract)
[17]	许宏发, 王武, 江淼, 等. 灌浆岩石锚杆拉拔变形和刚度的理论解析[J]. 岩土工程学报, 2011, 33(10): 1511-1516. XU H F, WANG W, JIANG M, et al. Theoretical analysis of pullout deformation and stiffness of grouted rockbolts[J]. Chinese Journal of Geotechnical Engineering, 2011, 33(10): 1511-1516. (in Chinese with English abstract)
[18]	郑卫锋, 邓海骥, 何金业. 输电线路岩石锚杆基础试验研究[J]. 建筑科学, 2012, 28 (9): 57-59. ZHENG W F, DENG H J, HE J Y. Experiment research of rock anchor foundation in transmission line[J]. Building Science, 2012, 28(9): 57-59. (in Chinese with English abstract)
[19]	冯自霞, 丁士君, 梅文明, 等. 输电铁塔岩石锚杆基础承载性能及影响因素试验研究[J]. 建筑科学, 2013, 29(3): 76-80. FENG Z X, DING S J, MEI W M, et al. Experimental study on bearing performance and influential factors for transmission-line rock anchor foundation[J]. Building Science, 2013, 29(3): 76-80. (in Chinese with English abstract)
[20]	侯中伟, 郑卫锋. 特高压输电线路岩石锚杆基础选型与设计[J]. 电力建设, 2014, 35(10): 64-68. HOU Z W, ZHENG W F. Type selection and design of rock anchor foundation in UHV transmission line[J]. Electric Power Construction, 2014, 35(10): 64-68. (in Chinese with English abstract)
[21]	程永锋, 赵江涛, 鲁先龙, 等. 特高压直流输电线路岩石锚杆群锚基础试验[J]. 中国电力, 2014, 47(12): 55-60. CHENG Y F, ZHAO J T, LU X L, et al. Field full-scale tests on group anchorage rock foundations of DC UHV transmission line project[J]. Electric Power, 2014, 47(12): 55-60. (in Chinese with English abstract)
[22]	鲁先龙, 杨文智, 郑卫锋, 等. 锚杆间距对岩石群锚基础抗拔力影响的试验研究[J]. 工业建筑, 2018, 48(4): 84-88. LU X L, YANG W Z, ZHENG W F, et al. Experimental research on effect of bolt spacing on uplift resistance for group anchor foundation in rocks[J]. Industrial Construction, 2018, 48(4): 84-88. (in Chinese with English abstract)
[23]	崔强, 邢明, 杨文智, 等. 喀斯特地区短桩锚杆复合基础现场抗拔试验及设计方法研究[J]. 岩石力学与工程学报, 2018, 37(11): 2621-2630. CUI Q, XING M, YANG W Z, et al. Field pull-out test and design method of the short pile and anchor composite foundation in the Karst area[J]. Chinese Journal of Rock Mechanics and Engineering, 2018, 37(11): 2621-2630. (in Chinese with English abstract)
[24]	张盈哲, 刘燕平, 章李刚, 等. 输电杆塔直群锚结合承台锚杆基础抗拔承载机理研究[J]. 电力勘测设计, 2021(10): 1-7. ZHANG Y Z, LIU Y P, ZHANG L G, et al. Study on the uplift resistance mechanism of rock foundation of transmissionwith combined direct and group bolts by numerical simulations[J]. Electric Power Survey & Design, 2021(10): 1-7. (in Chinese with English abstract)
[25]	丁士君, 杨文智, 朱照清, 等. 坚硬岩地基锚杆抗拔承载机制及破坏模式分析[J]. 工业建筑, 2023, 53(8): 191-198. DING S J, YANG W Z, ZHU Z Q, et al. Analysis on uplift bearing mechanisms and failure modes of anchor bolts in hard rock foundation[J]. Industrial Construction, 2023, 53(8): 191-198. (in Chinese with English abstract)
[26]	中华人民共和国住房和城乡建设部. 建筑基桩检测技术规范: JGJ 106-2014[S]. 北京: 中国建筑工业出版社, 2014. Ministry of Housing and Urban-Rural Development of the People's Republic of China. Technical code for testing of building foundation piles: JGJ 106-2014[S]. Beijing: China Architecture & Building Press, 2014. (in Chinese)
[27]	高磊, 周乐, 刘汉龙, 等. 灌注桩桩身变形高精度测量现场试验研究[J]. 岩土力学, 2021, 42(7): 2004-2014. GAO L, ZHOU L, LIU H L, et al. Field experimental study on the high-precision measurement of deformation of cast-in-place pile[J]. Rock and Soil Mechanics, 2021, 42(7): 2004-2014. (in Chinese with English abstract)
[28]	崔强, 童瑞铭, 刘生奎, 等. 基础尺寸对碎石土地基扩底基础上拔承载力影响的现场试验研究[J]. 土木建筑与环境工程, 2016, 38(6): 17-23. CUI Q, TONG R M, LIU S K, et al. Experimental analysis of the influence of foundation size parameters on the uplift bearing capacity of the spread foundation in gravel soil[J]. Journal of Civil, Architectural & Environmental Engineering, 2016, 38(6): 17-23. (in Chinese with English abstract)
[29]	崔强, 杨文智. 短桩-岩石锚杆复合基础研究技术报告[R]. 北京: 中国电力科学研究院, 2017. CUI Q, YANG W Z. Technical report on composite foundation of short pile and rock bolt research[R]. Beijing: China Electric Power Research Institute, 2017. (in Chinese)
[30]	崔强, 陈培. 宜昌石灰岩地基中的岩石锚杆基础现场试验技术报告[R]. 北京: 中国电力科学研究院, 2015. CUI Q, CHEN P. Technical report on field testing of rock anchor foundation in Yichang limestone foundation[R]. Beijing: China Electric Power Research Institute, 2015. (in Chinese)
[31]	杨文智, 郑卫锋, 满银, 等. 掏挖岩石锚杆复合基础上拔承载力计算中关键组合系数k₁与k₂的取值研究技术报告[R]. 北京: 中国电力科学研究院, 2014. YANG W Z, ZHENG W F, MAN Y, et al. Research on the coefficients of k₁ and k₂ for the foundation composed by digged foundation and rock bolt foundation[R]. Beijing: China Electric Power Research Institute, 2014. (in Chinese)