冷铸锚头性能光纤监测

吴俊; 周世良; 舒岳阶; 曹师宝; 周远航

doi:10.19818/j.cnki.1671-1637.2019.06.004

冷铸锚头性能光纤监测

doi: 10.19818/j.cnki.1671-1637.2019.06.004

重庆交通大学重庆西南水运工程科学研究所, 重庆 400016

基金项目:

国家自然科学基金项目 51508059

重庆市基础研究与前沿探索项目 cstc2018jcyjAX0345

重庆市教育委员会科学技术研究项目 KJQN201800739

宁波市交通运输科技项目 201704

内河航道整治技术交通行业重点实验室开放基金项目 NHHD-201502

详细信息

作者简介:
吴俊(1981-), 男, 江苏南通人, 重庆交通大学副研究员, 工学博士, 从事光纤智能结构监测研究

中图分类号: U446
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出版历程
- 收稿日期: 2019-05-19
- 刊出日期: 2019-12-25

Fiber monitoring of cold-casting anchor's performance

Chongqing Southwestern Research Institute of Water Engineering, Chongqing Jiaotong University, Chongqing 400016, China

More Information

Author Bio:
WU Jun (1981-), male, associate professor, PhD, 195575462@qq.com

摘要

摘要: 为监测冷铸锚头性能, 分析了其结构受力特点, 建立了锚头内钢丝与改性环氧填料微元体静载平衡模型, 分析了钢丝与环氧填料间黏接应力对钢丝应力分布特性的影响, 将锚头的失效表征为黏接应力的奇异变化, 提出了通过测量钢丝轴向多点应力分布实现对锚头性能状态无损监测的新方法; 针对LMLPES-7-211型锚头, 利用有限元方法分析了锚头内钢丝的轴向应力分布特性; 根据冷铸锚头内非均匀应变特性与恶劣环境要求, 提出了毛细管封装的应变均化拉丝塔光栅(DTG)测量方案, 开发了冷铸锚头植入式专用分布式应变传感器; 进行了缆索锚头性能状态监测模拟试验, 分别将2个分布式DTG应变传感器植入锚头1(性能正常)与锚头2(性能异常)内, 对锚头标准受力状态下钢丝分布式应变进行监测。分析结果表明: 锚头1、2内钢丝分布式应变呈现较大的差异性, 锚头1内应变衰减趋势较为平滑, 与有限元仿真结果比较误差小于5%, 锚头2应变衰减趋势平滑性不足, 且与有限元结果比较最大误差超过40%;性能衰退会导致近锚固始端区段的黏接应力大幅下降, 最大达到-2.55 MPa, 靠近分丝底板锚固区段的黏接应力大幅增加, 增加量达到3.25倍。通过设置黏接应力合理偏离阈值, 就可实现对锚头结构性能状态的在线监测与预警。
- 桥梁工程 /
- 性能监测 /
- 光纤分布式传感 /
- 冷铸锚头 /
- 黏接应力 /
- 应变均化拉丝塔光栅
Abstract: To monitor the performance of cold-casting anchor, the structural stress characteristics were analyzed, and the micro unit static balancing model of steel wire in the anchor and modified epoxy filler was established. The impact of bond stress between steel wire and epoxy filler on the steel wire stress distribution characteristics was analyzed, and the failure of anchor was characterized as a singular change of bond stress. A non-destructive monitoring method of anchor's performance status by measuring the axial multi-point stress distributions of steel wires was proposed. For the LMLPES-7-211 anchor, the axial stress distribution characteristics of steel wires in the anchor were analyzed by using the finite element method. According to the non-uniform strain characteristics and harsh environment requirements, a strain-equalized DTG measurement scheme using the capillary encapsulation was proposed, and a special implantable distributed strain sensor for cold-casting anchor was developed. The simulation tests of cable anchor's performance state monitoring were carried out, two DTG distributed strain sensors were implanted into anchor 1 with normal performance and anchor 2 with abnormal performance, respectively, and then the distributed strains of steel wires under the standard stress state of anchor were monitored. Analysis result shows that the distributed strains of steel wire in the anchors 1 and 2 present a big difference. The strain attenuation trend in the anchor 1 is smoother, and the error is less than 5% compared with the finite element simulation result. The smoothness of strain attenuation trend in anchor 2 is insufficient, and the maximum error is more than 40% compared with the finite element simulation result. The performance degradation causes the bond stress of near the anchoring section to drop sharply, reaching a maximum of-2.55 MPa, and the bond stress near the anchoring section of tapping base plate increases greatly, and the increment reaches 3.25 times. Therefore, by setting the reasonable threshold of bond stress, the online monitoring and early warning of anchor's performance state can be realized.
- bridge engineering /
- performance monitoring /
- fiber distributed sensing /
- cold-casting anchor /
- bond stress /
- strain-equalized DTG

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图 1 冷铸锚头结构剖面

Figure 1. Section of cold-casting anchor's structure

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图 2 单根钢丝受力原理

Figure 2. Force principle of single steel wire

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图 3 钢丝微元体受力原理

Figure 3. Force principle of steel wire micro unit

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图 4 锚头三维有限元模型

Figure 4. Three-dimensional finite element model of anchor

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图 5 有限元分析结果

Figure 5. Finite element analysis result

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图 6 应力分布趋势

Figure 6. Stress distribution trend

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图 7 测量方案

Figure 7. Measurement scheme

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图 8 测量原理

Figure 8. Measurement principle

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图 9 试验系统

Figure 9. Test system

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图 10 传感器位置

Figure 10. Placement of sensors

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图 11 缆索拉伸试验

Figure 11. Cable tension test

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图 12 DTG输出光谱

Figure 12. Output spectrums of DTGs

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图 13 拉伸试验结果

Figure 13. Tension test results

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表 1 LMLPES-7-211型锚头参数

Table 1. Parameters of LMLPES-7-211 anchor

参数	数值
锚杯外径/mm	305
锚杯长度/mm	555
锚圈外径/mm	405
锚圈高度/mm	180
钢丝直径/mm	7
钢丝数量/根	211

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表 2 DTG初始波长与标定系数

Table 2. Initial wavelengths and calibration coefficients of DTGs

锚固深度/cm	初始波长/nm(标定系数/μm)
锚固深度/cm	传感器1	传感器2	传感器3	传感器4
13	1 525.23(1.43)	1 541.28(1.42)	1 557.56(1.43)	1 573.76(1.44)
23	1 529.35(1.45)	1 545.35(1.44)	1 561.35(1.45)	1 577.67(1.42)
33	1 533.56(1.38)	1 549.22(1.37)	1 565.33(1.39)	1 581.56(1.38)
49	1 537.39(1.41)	1 553.45(1.38)	1 569.31(1.4)	1 585.54(1.42)

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表 3 各传感器测点应变与衰减量

Table 3. Strains and attenuation amounts of sensors

锚固深度/cm	应变/10^-6(衰减量/%)
锚固深度/cm	传感器1	传感器2	传感器3	传感器4
13	2 105(53.3)	1 982(55.9)	3 123(30.6)	2 862(36.4)
23	723(83.9)	686(84.7)	2 182(51.5)	2 115(53.0)
33	215(95.2)	208(95.3)	1 245(72.3)	1 362(69.7)
49	25(99.4)	189(9.6)	505(88.7)	486(89.2)

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表 4 各锚固段平均黏接应力

Table 4. Average bond stresses during each anchoring section

锚固区段/cm	平均黏接应力/MPa				锚头1黏接应力平均值/MPa	锚头2黏接应力平均值/MPa	偏离值/MPa(偏离率/%)
锚固区段/cm	传感器1所处钢丝	传感器2所处钢丝	传感器3所处钢丝	传感器4所处钢丝	锚头1黏接应力平均值/MPa	锚头2黏接应力平均值/MPa	偏离值/MPa(偏离率/%)
0~13	6.44	6.77	3.71	4.41	6.61	4.05	-2.55(-38.6)
13~23	4.83	4.53	3.29	2.61	4.68	2.95	-1.73(-36.9)
23~33	1.77	1.67	3.27	2.63	1.72	2.95	1.23(71.4)
33~49	0.42	0.42	1.61	1.91	0.42	1.76	1.35(325.2)

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参考文献(28)

[1]	叶觉明. 高强钢丝斜拉索工艺技术探讨[J]. 金属制品, 2002, 38(2): 11-14, 23. https://www.cnki.com.cn/Article/CJFDTOTAL-JSZP201202004.htm YE Jue-ming. Discussion on technical skill of high strength steel wire stay cable[J]. Metal Products, 2002, 38(2): 11-14, 23. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-JSZP201202004.htm
[2]	吴育苗, 蒋湘成, 朱利明. 斜拉桥斜拉索体系病害分析与处理方案[J]. 世界桥梁, 2013, 41(3): 77-80, 84. https://www.cnki.com.cn/Article/CJFDTOTAL-GWQL201303017.htm WU Yu-miao, JIANG Xiang-cheng, ZHU Li-ming. Deterioration analysis of stay cable system of cable-stayed bridge and the dealing scheme[J]. World Bridge, 2013, 41(3): 77-80, 84. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-GWQL201303017.htm
[3]	刘海基. 斜拉桥拉索病害成因及对策分析[J]. 城市建筑, 2013(24): 288. doi: 10.3969/j.issn.1673-0232.2013.24.260 LIU Hai-ji. Analysis of cable disease causes and solutions of cable-stayed bidge[J]. City Building, 2013(24): 288. (in Chinese). doi: 10.3969/j.issn.1673-0232.2013.24.260
[4]	李权, 习燕, 赵轶才, 等. 新型斜拉索冷铸锚灌注料试验研究[J]. 公路交通技术, 2011(1): 86-89. doi: 10.3969/j.issn.1009-6477.2011.01.022 LI Quan, XI Yan, ZHAO Yi-cai, et al. Experimental study on neotype filler for stayed-cable chilled casting anchor[J]. Technology of Highway and Transport, 2011(1): 86-89. (in Chinese). doi: 10.3969/j.issn.1009-6477.2011.01.022
[5]	卢剑峰, 罗艺红, 陈艺玲, 等. 冷铸锚650 t张拉杆失效分析[J]. 预应力技术, 2014(2): 37-39. LU Jian-feng, LUO Yi-hong, CHEN Yi-ling, et al. Failure analysis of 650 tons tension rod of cold casting anchor[J]. Prestress Technology, 2014(2): 37-39. (in Chinese).
[6]	HAN S H, LEE W S, BANG M S. Probabilistic optimal safety with minimum life-cycle cost based on stochastic finite element analysis of steel cable-stayed bridges[J]. International Journal of Steel Structures, 2011, 11(3): 335-349. doi: 10.1007/s13296-011-3008-9
[7]	CHOI D H, PARK W S. Tension force estimation of extradosed bridge cables oscillating nonlinearly under gravity effects[J]. International Journal of Steel Structures, 2011, 11(3): 383-394. doi: 10.1007/s13296-011-3012-0
[8]	MOZOS C M, APARICIO A C. Numerical and experimental study on the interaction cable structure during the failure of a stay in a cable stayed bridge[J]. Engineering Structures, 2011, 33(8): 2330-2341. doi: 10.1016/j.engstruct.2011.04.006
[9]	BOARETTO N, CENTENO T M. Automated detection of welding defects in pipelines from radiographic images DWDI[J]. NDT and E International, 2017, 86(1): 7-13.
[10]	SHAO Jia-xin, DU Dong, CHANG Bao-hua, et al. Automatic weld defect detection based on potential defect tracking in real-time radiographic image sequence[J]. NDT and E International, 2012, 46(1): 14-21.
[11]	ZOU Yi-rong, DU Dong, CHANG Bao-hua, et al. Automatic weld defect detection method based on Kalman filtering for real-time radiographic inspection of spiral pipe[J]. NDT and E International, 2015, 72: 1-9. doi: 10.1016/j.ndteint.2015.01.002
[12]	ZHAO Yi, LI Xiao-min, LIN Lei, et al. Measurements of coating density using ultrasonic reflection coefficient phase spectrum[J]. Ultrasonics, 2011, 51(5): 596-601. doi: 10.1016/j.ultras.2010.12.015
[13]	董泽蛟, 李生龙, 温佳宇, 等. 基于光纤光栅测试技术的沥青路面温度场实测[J]. 交通运输工程学报, 2014, 14(2): 1-6, 13. doi: 10.3969/j.issn.1671-1637.2014.02.002 DONG Ze-jiao, LI Sheng-long, WEN Jia-yu, et al. Real-time temperature field measurement of asphalt pavement based on fiber Bragg grating measuring technology[J]. Journal of Traffic and Transportation Engineering, 2014, 14(2): 1-6, 13. (in Chinese). doi: 10.3969/j.issn.1671-1637.2014.02.002
[14]	邓年春, 周智, 龙跃, 等. 光纤光栅冷铸镦头锚拉索及其在桥梁中应用[J]. 预应力技术, 2007(3): 3-6, 24. DENG Nian-chun, ZHOU Zhi, LONG Yue, et al. Fiber Bragg grating cold casting twist anchor cable and its application in bridges[J]. Prestress Technology, 2007(3): 3-6, 24. (in Chinese).
[15]	HO S C M, LI Wei-jie, WANG Bo, et al. A load measuring anchor plate for rock bolt using fiber optic sensor[J]. Smart Materials and Structures, 2017, 26: 1-7.
[16]	YANG Ming-hong, BAI Wei, GUO Hui-yong, et al. Huge capacity fiber-optic sensing network based on ultra-weak draw tower gratings[J]. Photonic Sensors, 2016, 6(1): 26-41. doi: 10.1007/s13320-015-0298-0
[17]	WANG Yun-miao, GONG Jian-min, WANG D Y, et al. A quasi-distributed sensing network with time-division-multiplexed fiber Bragg gratings[J]. IEEE Photonics Technology Letters, 2011, 23(2): 70-72. doi: 10.1109/LPT.2010.2089676
[18]	RAO Y J, RIBEIRO A B L, JACKSON D A, et al. Simultaneous spatial, time and wavelength division multiplexed in-fibre grating sensing network[J]. Optics Communications, 1996, 125: 53-58. doi: 10.1016/0030-4018(95)00722-9
[19]	余海湖, 郑羽, 郭会勇, 等. 光纤光栅在线制备技术研究进展[J]. 功能材料, 2014, 12(5): 12001-12005. https://www.cnki.com.cn/Article/CJFDTOTAL-GNCL201412001.htm YU Hai-hu, ZHENG Yu, GUO Hui-yong, et al. Research progress in online preparation techniques of fiber Bragg gratings on optical fiber drawing tower[J]. Functional Materials, 2014, 12(5): 12001-12005. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-GNCL201412001.htm
[20]	李剑芝, 杜彦良, 刘晨曦. 采用在线成型工艺的光纤光栅传感器[J]. 光学精密工程, 2009, 17(9): 2069-2075. doi: 10.3321/j.issn:1004-924X.2009.09.001 LI Jian-zhi, DU Yan-liang, LIU Chen-xi. FBG strain sensor based on online forming[J]. Optics and Precision Engineering, 2009, 17(9): 2069-2075. (in Chinese). doi: 10.3321/j.issn:1004-924X.2009.09.001
[21]	LINDNER E, CANNING J, CHOJETZKI C, et al. Post-hydrogen-loaded draw tower fiber Bragg gratings and their thermal regeneration[J]. Applied Optics, 2011, 50(17): 2519-2522. doi: 10.1364/AO.50.002519
[22]	ASLUND M L, CANNING J, STEVENSON M, et al. Thermal stabilization of type I fiber Bragg gratings for operation up to 600 degrees[J]. Optics Letters, 2010, 35(4): 586-588. doi: 10.1364/OL.35.000586
[23]	XU Ru-quan, GUO Hui-yong, LIANG Lei. Distributed fiber optic interferometric geophone system based on draw tower gratings[J]. Photonic Sensors, 2017, 7(3): 246-252. doi: 10.1007/s13320-017-0408-2
[24]	JOHNSON D. Draw-tower process creates high-quality FBG arrays[J]. Laser Focus World, 2012, 48(10): 53-56.
[25]	吴俊, 陈伟民, 舒岳阶, 等. 锚头植入式应变均化光纤布喇格光栅测力传感器[J]. 光子学报, 2015, 44(7): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB201507015.htm WU Jun, CHEN Wei-min, SHU Yue-jie, et al. Embedded strain homogenized FBG sensor for smart cables[J]. Acta Photonica Sinica, 2015, 44(7): 1-6. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB201507015.htm
[26]	吴俊, 陈伟民, 余葵, 等. 非栅区封装光纤布喇格光栅应变传感特性研究[J]. 光子学报, 2016, 45(2): 1-5. https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB201602016.htm WU Jun, CHEN Wei-min, YU Kui, et al. Strain sensing properties of grating ends packaged FBG sensors[J]. Acta Photonica Sinica, 2016, 45(2): 1-5. (in Chinese). https://www.cnki.com.cn/Article/CJFDTOTAL-GZXB201602016.htm
[27]	WANG Hua-ping, ZHOU Zhi. Advances of strain transfer analysis of optical fibre sensors[J]. Pacific Science Review, 2014, 16: 8-18.
[28]	XUE Zi-qiu, PARK H, KIYAMA T, et al. Effects of hydrostatic pressure on strain measurement with distributed optical fiber sensing system[J]. Energy Procedia, 2014: 4003-4009.