Effects of diameter of borehole backfill on strain coupling of sensing optical cable

SHI Songge; SHI Bin; LIU Suping; ZHANG Chengcheng; GU Kai; HE Jianhui

doi:10.11779/CJGE20211451

Volume 45 Issue 1

Turn off MathJax

Article Contents

Abstract

References

Supplements

Chinese Journal of Geotechnical Engineering > 2023 > 45(1): 162-170. > DOI: 10.11779/CJGE20211451

SHI Songge, SHI Bin, LIU Suping, ZHANG Chengcheng, GU Kai, HE Jianhui. Effects of diameter of borehole backfill on strain coupling of sensing optical cable[J]. Chinese Journal of Geotechnical Engineering, 2023, 45(1): 162-170. DOI: 10.11779/CJGE20211451

Citation:

PDF (2675 KB)

Effects of diameter of borehole backfill on strain coupling of sensing optical cable

School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China

More Information

Received Date: October 27, 2021
Available Online: February 03, 2023
Published Date: October 27, 2021

Graphical Abstract

Abstract

Abstract

The borehole full-section optical fiber monitoring technology has been widely applied in the monitoring of geological disasters such as ground subsidence and mine collapse. The strain coupling between the borehole backfill and the directly buried sensing cable is the key to the influence of the accuracy of optical fiber monitoring results. The strain coupling between the fiber optic cable and the backfill of sand with different particle sizes (0.5~4 mm) under the confining pressures of 0~1.0 MPa is investigated by using the coupling analysis device of controllable confining pressure cable and backfill. The results show that under the same confining pressure and pull-out displacement, the strain coupling between the optical cable and the sand decreases while the particle size increases, that is, the coupling between the sand of 0.5~1 mm and the strain sensing optical cable is the strongest. Using 10000 με as the maximum strain monitoring range of sensing cable, the strain coupling between the sensing cable and the sand soil is evaluated. When the deformation coordination coefficient of the fiber optic cable and the sand reaches 0.9, the critical confining pressures with particle sizes of 0.5~1, 1~2, and 2~4 mm are 0.14, 0.33, and 0.52 MPa in order. The interface shear stress between the fiber optic cable and the sand first increases and then decreases. With the increase of the pull-out displacement, the peak value and the transfer depth of the interface shear stress increase. The results provide a scientific basis for determining the depth of the critical confining pressure of the borehole full-section optical fiber monitoring.
- distributed fiber-optic sensing,
- borehole backfill,
- interface shear stress,
- coupling,
- particle size

FullText(HTML)

References (24)

References

[1]	施斌, 张丹, 朱鸿鹄. 地质与岩土工程分布式光纤监测技术[M]. 北京: 科学出版社, 2019. SHI Bin, ZHANG Dan, ZHU Honghu. Distributed Fiber Optic Sensing for Geoengineering Monitoring[M]. Beijing: Science Press, 2019. (in Chinese)
[2]	施斌, 张丹, 王宝军. 地质与岩土工程分布式光纤监测技术及其发展[C]//工程地质力学创新与发展暨工程地质研究室成立50周年学术研讨会. 北京, 2008. SHI Bin, ZHANG Dan, WANG Bao-jun. Distributed optical fiber monitoring technologies of geological and geotechnical engineering and its development[C]// Proceedings of the Symposium on Innovation and Development of Engineering Geomechanics And the 50th Anniversary of Engineering Geology Laboratory. Beijing, 2008. (in Chinese)
[3]	卢毅, 施斌, 魏广庆. 基于BOTDR与FBG的地裂缝定点分布式光纤传感监测技术研究[J]. 中国地质灾害与防治学报, 2016, 27(2): 103-109. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGDH201602016.htm LU Yi, SHI Bin, WEI Guangqing. BOTDR and FBG fixed-point distributed optical fiber sensor monitoring technology for ground fissures[J]. The Chinese Journal of Geological Hazard and Control, 2016, 27(2): 103-109. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGDH201602016.htm
[4]	施斌, 徐洪钟, 张丹, 等. BOTDR应变监测技术应用在大型基础工程健康诊断中的可行性研究[J]. 岩石力学与工程学报, 2004, 23(3): 493-499. doi: 10.3321/j.issn:1000-6915.2004.03.025 SHI Bin, XU Hongzhong, ZHANG Dan, et al. Feasibility study on application of botdr to health monitoring for large infrastructure engineering[J]. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(3): 493-499. (in Chinese) doi: 10.3321/j.issn:1000-6915.2004.03.025
[5]	孙义杰, 张丹, 童恒金, 等. 分布式光纤监测技术在三峡库区马家沟滑坡中的应用[J]. 中国地质灾害与防治学报, 2013, 24(4): 97-102. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGDH201304024.htm SUN Yijie, ZHANG Dan, TONG Hengjin, et al. Research of distributed fiber optic sensing technology in monitoring of Majiagou landslide of Three Gorges[J]. The Chinese Journal of Geological Hazard and Control, 2013, 24(4): 97-102. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGDH201304024.htm
[6]	吴静红, 刘浩, 杨鹏, 等. 基于光频域反射计技术的混凝土裂缝识别与监测[J]. 激光与光电子学进展, 2019, 56(24): 140-147. https://www.cnki.com.cn/Article/CJFDTOTAL-JGDJ201924017.htm WU Jinghong, LIU Hao, YANG Peng, et al. Identification and monitoringof concrete cracks based on optical frequency domain ReflectometryTechnique[J]. Laser & Optoelectronics Progress, 2019, 56(24): 140-147. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-JGDJ201924017.htm
[7]	朴春德, 施斌, 朱友群, 等. 钻孔灌注桩压缩变形BOTDR分布式检测[J]. 水文地质工程地质, 2008, 35(4): 80-83. doi: 10.3969/j.issn.1000-3665.2008.04.019 PIAO Chunde, SHI Bin, ZHU Youqun, et al. Distributed monitoring of bored pile compression deformation based on BOTDR[J]. Hydrogeology & Engineering Geology, 2008, 35(4): 80-83. (in Chinese) doi: 10.3969/j.issn.1000-3665.2008.04.019
[8]	王德洋, 朱鸿鹄, 吴海颖, 等. 地层塌陷作用下埋地管道光纤监测试验研究[J]. 岩土工程学报, 2020, 42(6): 1125-1131. doi: 10.11779/CJGE202006017 WANG Deyang, ZHU Honghu, WU Haiying, et al. Experimental study on buried pipeline instrumented with fiber optic sensors under ground collapse[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(6): 1125-1131. (in Chinese) doi: 10.11779/CJGE202006017
[9]	张诚成, 施斌, 朱鸿鹄, 等. 地面沉降分布式光纤监测土–缆耦合性分析[J]. 岩土工程学报, 2019, 41(9): 1670-1678. doi: 10.11779/CJGE201909011 ZHANG Chengcheng, SHI Bin, ZHU Honghu, et al. Theoretical analysis of mechanical coupling between soil and fiber optic strain sensing cable for distributed monitoring of ground settlement[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(9): 1670-1678. (in Chinese) doi: 10.11779/CJGE201909011
[10]	许星宇, 朱鸿鹄, 张巍, 等. 基于光纤监测的边坡应变场可视化系统研究[J]. 岩土工程学报, 2017, 39(增刊1): 96-100. doi: 10.11779/CJGE2017S1019 XU Xingyu, ZHU Honghu, ZHANG Wei, et al. Development of fiber optic monitoring-based visualization system for strain fields of slopes[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(S1): 96-100. (in Chinese) doi: 10.11779/CJGE2017S1019
[11]	何宁, 王国利, 何斌, 等. 高面板堆石坝内部水平位移新型监测技术研究[J]. 岩土工程学报, 2016, 38(增刊2): 24-29. doi: 10.11779/CJGE2016S2004 HE Ning, WANG Guoli, HE Bin, et al. New technology for inner horizontal displacement monitoring in high concrete face rockfill dam[J]. Chinese Journal of Geotechnical Engineering, 2016, 38(S2): 24-29. (in Chinese) doi: 10.11779/CJGE2016S2004
[12]	张丹, 张平松, 施斌, 等. 采场覆岩变形与破坏的分布式光纤监测与分析[J]. 岩土工程学报, 2015, 37(5): 952-957. doi: 10.11779/CJGE201505023 ZHANG Dan, ZHANG Pingsong, SHI Bin, et al. Monitoring and analysis of overburden deformation and failure using distributed fiber optic sensing[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(5): 952-957. (in Chinese) doi: 10.11779/CJGE201505023
[13]	WU J H, JIANG H T, SU J W, et al. Application of distributed fiber optic sensing technique in land subsidence monitoring[J]. Journal of Civil Structural Health Monitoring, 2015, 5(5): 587-597.
[14]	施斌, 顾凯, 魏广庆, 等. 地面沉降钻孔全断面分布式光纤监测技术[J]. 工程地质学报, 2018, 26(2): 356-364. SHI Bin, GU Kai, WEI Guangqing, et al. Full section monitoring of land subsidence borehole using distributed fiber optic sensing techniques[J]. Journal of Engineering Geology, 2018, 26(2): 356-364. (in Chinese)
[15]	刘苏平, 施斌, 张诚成, 等. 连云港徐圩地面沉降BOTDR监测与评价[J]. 水文地质工程地质, 2018, 45(5): 158-164. https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201805023.htm LIU Suping, SHI Bin, ZHANG Chengcheng, et al. Monitoring and evaluation of land subsidence based on BOTDR in Xuwei near Lianyungang[J]. Hydrogeology & Engineering Geology, 2018, 45(5): 158-164. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201805023.htm
[16]	佘骏宽, 朱鸿鹄, 张诚成, 等. 传感光纤-砂土界面力学性质的试验研究[J]. 工程地质学报, 2014, 22(5): 855-860. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201405014.htm SHE Junkuan, ZHU Honghu, ZHANG Chengcheng, et al. Experiment study on mechanical properties of interface between sensing optical fiber and sand[J]. Journal of Engineering Geology, 2014, 22(5): 855-860. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201405014.htm
[17]	ZHANG C C, ZHU H H, SHI B, et al. Interfacial characterization of soil-embedded optical fiber for ground deformation measurement[J]. Smart Materials and Structures, 2014, 23(9): 095022.
[18]	ZHANG C C, ZHU H H, SHI B. Role of the interface between distributed fibre optic strain sensor and soil in ground deformation measurement[J]. Scientific Reports, 2016, 6: 36469.
[19]	张诚成, 施斌, 刘苏平, 等. 钻孔回填料与直埋式应变传感光缆耦合性研究[J]. 岩土工程学报, 2018, 40(11): 1959-1967. doi: 10.11779/CJGE201811001 ZHANG Chengcheng, SHI Bin, LIU Suping, et al. Mechanical coupling between borehole backfill and fiber-optic strain-sensing cable[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(11): 1959-1967. (in Chinese) doi: 10.11779/CJGE201811001
[20]	卢毅, 施斌, 于军, 等. 地面变形分布式光纤监测模型试验研究[J]. 工程地质学报, 2015, 23(5): 896-901. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201505012.htm LU Yi, SHI Bin, YU Jun, et al. Model test on distributed optical fiber monitoring of land subsidence and ground fissures[J]. Journal of Engineering Geology, 2015, 23(5): 896-901. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201505012.htm
[21]	HAUSWIRTH D, ITEN M, RICHLI R, et al. Fibre optic cable and micro-anchor pullout tests in sand[C]//Proceedings of the 7th International Conference on Physical Modelling in Geotechnics (ICPMG 2010). Zurich, 2010.
[22]	张松, 施斌, 张诚成, 等. 低围压下锚固点应变传感光缆与土体变形耦合性试验研究[J]. 工程地质学报, 2019, 27(6): 1456-1463. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201906028.htm ZHANG Song, SHI Bin, ZHANG Chengcheng, et al. Experimental study on mechanical coupling between anchored strain sensing optical cable and soil deformation under low confining pressures[J]. Journal of Engineering Geology, 2019, 27(6): 1456-1463. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201906028.htm
[23]	刘波, 胡卸文, 白凯文, 等. 基于界面本构模型的锚杆张拉受力分析[J]. 长江科学院院报, 2019, 36(6): 77-82. https://www.cnki.com.cn/Article/CJFDTOTAL-CJKB201906018.htm LIU Bo, HU Xiewen, BAI Kaiwen, et al. Stress analysis of anchor in tension based on interface constitutive model[J]. Journal of Yangtze River Scientific Research Institute, 2019, 36(6): 77-82. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-CJKB201906018.htm
[24]	姚强岭, 王伟男, 孟国胜, 等. 树脂锚杆不同锚固长度锚固段受力特征试验研究[J]. 采矿与安全工程学报, 2019, 36(4): 643-649. https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201904001.htm YAO Qiangling, WANG Weinan, MENG Guosheng, et al. Experimental study on mechanical characteristics of resin bolt anchoring section with different anchorage lengths[J]. Journal of Mining & Safety Engineering, 2019, 36(4): 643-649. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-KSYL201904001.htm