非饱和土水分迁移感测的主动加热光纤光栅法试验研究

刘喜凤; 朱鸿鹄; 王家琛; 李杰; 王静; 曹鼎峰; 施斌

doi:10.11779/CJGE202208009

非饱和土水分迁移感测的主动加热光纤光栅法试验研究 English Version

刘喜凤^1,,
朱鸿鹄^{1, 2, ,},
王家琛^{1, 3, 4},
李杰¹,
王静¹,
曹鼎峰^{2, 5},
施斌¹

1.
南京大学地球科学与工程学院, 江苏南京 200023
2.
广东省海洋土木工程重点实验室, 广东广州 510275
3.
中国长江三峡集团雄安分公司, 河北雄安新区 071700
4.
长江三峡集团雄安能源有限公司, 河北雄安新区 071700
5.
中山大学土木工程学院, 广东广州 510275

基金项目:

国家重点研发计划项目 2018YFC1505104

广东省海洋土木工程重点实验室开放基金项目 LMCE202006

软弱土与环境土工教育部重点实验室开放基金项目 2019P05

详细信息

作者简介:
刘喜凤(1998—)，女，硕士研究生，主要从事地质与岩土工程监测方面的研究工作。E-mail: liuxf@smail.nju.edu.cn

通讯作者:
朱鸿鹄，E-mail: zhh@nju.edu.cn

中图分类号: TU411
计量
- 文章访问数: 214
- HTML全文浏览量: 23
- PDF下载量: 179
出版历程
- 收稿日期: 2021-05-15
- 网络出版日期: 2022-09-22
- 刊出日期: 2022-07-31

Experimental study on actively heated fiber Bragg grating method for sensing seepage in unsaturated soils

LIU Xi-feng^1,,
ZHU Hong-hu^{1, 2, ,},
WANG Jia-chen^{1, 3, 4},
LI Jie¹,
WANG Jing¹,
CAO Ding-feng^{2, 5},
SHI Bin¹

1.
School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
2.
Guangdong Key Laboratory of Marine Civil Engineering, Guangzhou 510275, China
3.
Xiong'an Branch, China Three Gorges Corporation, Xiong'an 071700, China
4.
Yangtze Three Gorges Group Xiong'an Energy Company Limited, Xiong'an 071700, China
5.
School of Civil Engineering, Sun Yat-sen University, Guangzhou 510275, China

摘要

摘要: 非饱和土水分迁移是诱发多种地质灾害和环境岩土问题的重要因素，对其机理的认识因测试技术的不足尚不明确。为探究主动加热光纤光栅（AH-FBG）法监测非饱和土水分迁移的效果，分析单探针和双探针AH-FBG法的误差来源及分布特征，开展了一组室内土柱试验。在试验中同时采用AH-FBG法和传统的频域反射（FDR）法监测毛细水上升和水分蒸发的全过程，对比单探针法和双探针法的监测精度，分析不同方法的适用工况。结果表明：基于单探针AH-FBG的3种数据分析方法中，热导率法的监测精度最高，但是单探针法在监测毛细水上升过程中，当湿润锋刚没过探针感测位置时，受纵向传热的影响会使得测量的含水率值偏低；相比于单探针法，双探针法受纵向传热的影响更大，监测土体水分迁移有较大误差，误差大小与测点位置处的土体含水率值及土柱纵剖面的含水率分布情况有关；为减小纵向传热影响，从传感器结构和数据处理两方面提出了AH-FBG法的改进措施。
- 主动加热光纤(AHFO)法 /
- 单探针法 /
- 双探针法 /
- 蒸发 /
- 毛细水
Abstract: The seepage in unsaturated soils is a key factor that induces various geohazards and geoenvironmental problems, but the mechanism has not been clearly understood due to the limitations of measuring techniques. A series of soil column tests are carried out to study the performance of actively heated fiber Bragg grating (AH-FBG) in monitoring the seepage in unsaturated soils and analyze the error sources and distribution characteristics of the single-probe and dual-probe methods. Both the AH-FBG and the frequency domain reflectometry are used to monitor the whole process of rise of capillary water and water evaporation. The monitoring accuracy of the single-probe and dual-probe methods is compared, and the applicable conditions of different methods are analyzed. The results show that the thermal conductivity method has the highest accuracy among the three data analysis methods based on the single-probe AH-FBG method. However, when the wetting front just exceeds the sensing section of the probe in the process of the rise of capillary water, the measured moisture content will be low due to the influences of longitudinal heat transfer. Compared with the single-probe method, the dual-probe method is more affected by longitudinal heat transfer and has a larger error in monitoring the seepage. The error is related to the value of moisture content of soils at the position of the measuring point and the distribution of moisture content of soils in the vertical profile of the soil column. In order to reduce the influences of longitudinal heat transfer, the improvement measures of AH-FBG method are proposed from two aspects of sensor structure and data processing.
- actively heated fiber optic method /
- single-probe method /
- dual-probe method /
- evaporation /
- capillary water

HTML全文

图 1 单探针AH-FBG法监测原理

Figure 1. Principle of monitoring by single-probe AH-FBG method

下载: 全尺寸图片幻灯片

图 2 双探针AH-FBG法监测原理

Figure 2. Principle of monitoring by dual-probe AH-FBG method

下载: 全尺寸图片幻灯片

图 3 土样粒径分布曲线

Figure 3. Grain-size distribution curve of soil sample

下载: 全尺寸图片幻灯片

图 4 试验装置示意图

Figure 4. Schematic diagram of experimental equipment

下载: 全尺寸图片幻灯片

图 5 单探针法标定曲线

Figure 5. Calibration curves by single-probe method

下载: 全尺寸图片幻灯片

图 6 单探针法测量值与FDR法测量值比较

Figure 6. Comparison of single-probe method and FDR method

下载: 全尺寸图片幻灯片

图 7 单探针法测量效果

Figure 7. Predicted effect by single-probe method

下载: 全尺寸图片幻灯片

图 8 体积比热容与含水率

Figure 8. Volume specific heat capacity and water content

下载: 全尺寸图片幻灯片

图 9 双探针法测量值与FDR法测量值比较

Figure 9. Comparison between dual-probe method and FDR method

下载: 全尺寸图片幻灯片

图 10 毛细水上升过程和蒸发过程水分迁移趋势

Figure 10. Changing trend of moisture migration during capillary rise and evaporation

下载: 全尺寸图片幻灯片

图 11 双探针法含水率测量误差分布

Figure 11. Error distribution of water content measured by dual-probe method

下载: 全尺寸图片幻灯片

图 12 纵向传热示意图

Figure 12. Schematic diagram of vertical heat transfer

下载: 全尺寸图片幻灯片

表 1 单探针法标定曲线拟合公式及拟合效果

Table 1 Fitting formula and results of calibration curve by single-probe method

分析方法	FBG高程/cm	y= ax^b		R²	RMSE
分析方法	FBG高程/cm	系数a	指数b	R²	RMSE
最大升温值法	45	6.925	-0.301	0.958	2.915℃
	35	9.951	-0.342	0.99	0.877 ℃
	25	9.696	-0.28	0.98	1.407 ℃
	15	9.29	-0.324	0.943	0.907 ℃
	5	8.032	-0.358	0.992	0.271 ℃
累计升温值法	45	4798	-0.261	0.953	1516℃·s
	35	6680	-0.293	0.989	485.8 ℃·s
	25	6403	-0.246	0.988	515.3 ℃·s
	15	6241	-0.28	0.916	598.0 ℃·s
	5	5519	-0.31	0.992	146.3 ℃·s
热导率法	45	5.333	0.525	0.958	0.108 W·m^-1·℃^-1
	35	3.002	0.598	0.992	0.087 W·m^-1·℃^-1
	25	2.899	0.473	0.958	0.114 W·m^-1·℃^-1
	15	3.312	0.557	0.975	0.102 W·m^-1·℃^-1
	5	5.024	0.657	0.988	0.103 W·m^-1·℃^-1

下载: 导出CSV

参考文献(34)

[1]	邢鲜丽, 李同录, 李萍, 等. 黄土抗剪强度与含水率的变化规律[J]. 水文地质工程地质, 2014, 41(3): 53-59, 97. https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201403012.htm XING Xian-li, LI Tong-lu, LI Ping, et al. Variation regularities of loess shear strength with the moisture content[J]. Hydrogeology and Engineering Geology, 2014, 41(3): 53-59, 97. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SWDG201403012.htm
[2]	CHEN H, LEE C F, LAW K T. Causative mechanisms of rainfall-induced fill slope failures[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2004, 130(6): 593-602. doi: 10.1061/(ASCE)1090-0241(2004)130:6(593)
[3]	LU N, LIKOS W J. Unsaturated Soil Mechanics[M]. Hoboken: John Wiley & Sons Inc, 2004.
[4]	TANG C S, CUI Y J, SHI B, et al. Desiccation and cracking behaviour of clay layer from slurry state under wetting-drying cycles[J]. Geoderma, 2011, 166(1): 111-118. doi: 10.1016/j.geoderma.2011.07.018
[5]	SERRARENS D, MACINTYRE J L, HOPMANS J W, et al. Soil moisture calibration of TDR multilevel probes[J]. Scientia Agricola, 2000, 57(2): 349-354. doi: 10.1590/S0103-90162000000200024
[6]	NADLER A, GAMLIEL A, PERETZ I. Practical aspects of salinity effect on TDR-measured water content: a field study[J]. Soil Science Society of America Journal, 1999, 63(5): 1070-1076. doi: 10.2136/sssaj1999.6351070x
[7]	EVETT S R, STEINER J L. Precision of neutron scattering and capacitance type soil water content gauges from field calibration[J]. Soil Science Society of America Journal, 1995, 59(4): 961-968. doi: 10.2136/sssaj1995.03615995005900040001x
[8]	FRIEDMAN S P. Soil properties influencing apparent electrical conductivity: a review[J]. Computers and Electronics in Agriculture, 2005, 46(1/2/3): 45-70. https://www.sciencedirect.com/science/article/pii/S0168169904001255
[9]	ANDERSSON P M, LINDER B G, NILSSON N R. Radar system for mapping internal erosion in embankment dams[J]. International Water Power and Dam Construction, 1991, 43(7): 11-16.
[10]	BRISTOW K L, KLUITENBERG G J, GODING C J, et al. A small multi-needle probe for measuring soil thermal properties, water content and electrical conductivity[J]. Computers and Electronics in Agriculture, 2001, 31(3): 265-280. doi: 10.1016/S0168-1699(00)00186-1
[11]	OCHSNER T E, HORTON R, REN T S. Use of the dual-probe heat-pulse technique to monitor soil water content in the vadose zone[J]. Vadose Zone Journal, 2003, 2(4): 572-579. doi: 10.2136/vzj2003.5720
[12]	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 Hong-hu. Distributed Fiber Optic Sensing for Geoengineering Monitoring[M]. Beijing: Science Press, 2019. (in Chinese)
[13]	SAYDE C, GREGORY C, GIL-RODRIGUEZ M, et al. Feasibility of soil moisture monitoring with heated fiber optics[J]. Water Resources Research, 2010, 46(6): W06201. doi: 10.1029/2009WR007846
[14]	曹鼎峰, 施斌, 严珺凡, 等. 基于C-DTS的土壤含水率分布式测定方法研究[J]. 岩土工程学报, 2014, 36(5): 910-915. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201405021.htm CAO Ding-feng, SHI Bin, YAN Jun-fan, et al. Distributed method for measuring moisture content of soils based on C-DTS[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(5): 910-915. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201405021.htm
[15]	BENÍTEZ-BUELGA J, SAYDE C, RODRÍGUEZ-SINOBAS L, et al. Heated fiber optic distributed temperature sensing: a dual-probe heat-pulse approach[J]. Vadose Zone Journal, 2014, 13(11): 1-10. doi: 10.2136/vzj2014.02.0014
[16]	YAN J F, SHI B, ZHU H H, et al. A quantitative monitoring technology for seepage in slopes using DTS[J]. Engineering Geology, 2015, 186: 100-104. doi: 10.1016/j.enggeo.2015.01.001
[17]	LI M, SI B C, HU W, et al. Single-probe heat pulse method for soil water content determination: comparison of methods[J]. Vadose Zone Journal, 2016, 15(7): 1-13. https://pubs.geoscienceworld.org/vzj/article-abstract/15/7/vzj2016.01.0004/246457/Single-Probe-Heat-Pulse-Method-for-Soil-Water
[18]	胡优, 李敏, 任姮烨, 等. 基于加热光纤分布式温度传感器的土壤含水率测定方法[J]. 农业工程学报, 2019, 35(10): 42-49. doi: 10.11975/j.issn.1002-6819.2019.10.006 HU You, LI Min, REN Heng-ye, et al. Measurement of soil water content using distributed temperature sensor with heated fiber optics[J]. Transactions of the Chinese Society of Agricultural Engineering, 2019, 35(10): 42-49. (in Chinese) doi: 10.11975/j.issn.1002-6819.2019.10.006
[19]	CAO D F, SHI B, ZHU H H, et al. A soil moisture estimation method using actively heated fiber Bragg grating sensors[J]. Engineering Geology, 2018, 242: 142-149. doi: 10.1016/j.enggeo.2018.05.024
[20]	段超喆, 施斌, 曹鼎峰, 等. 一种准分布式内加热刚玉管FBG渗流速率监测方法[J]. 防灾减灾工程学报, 2018, 38(3): 504-510. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXK201803014.htm DUAN Chao-zhe, SHI Bin, CAO Ding-feng, et al. A quasi-distributed seepage velocity monitoring method using FBG embedded in internal heated alundum tube[J]. Journal of Disaster Prevention and Mitigation Engineering, 2018, 38(3): 504-510. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-DZXK201803014.htm
[21]	王家琛, 朱鸿鹄, 王静, 等. 基于主动加热光纤法的毛细阻滞入渗模型试验研究[J]. 岩土工程学报, 2021, 43(1): 147-155. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC202101022.htm WANG Jia-chen, ZHU Hong-hu, WANG Jing, et al. Laboratory model tests on capillary barrier infiltration using actively heated fiber optic method[J]. Chinese Journal of Geotechnical Engineering, 2021, 43(1): 147-155. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC202101022.htm
[22]	CAO D F, ZHU H H, WU B, et al. Investigating temperature and moisture profiles of seasonally frozen soil under different land covers using actively heated fiber Bragg grating sensors[J]. Engineering Geology, 2021, 290: 106197. doi: 10.1016/j.enggeo.2021.106197
[23]	陈强, 刁少波, 孙建业, 等. 热脉冲探针-时域反射技术测量含水合物沉积物的热导率及水合物饱和度[J]. 岩矿测试, 2013(1): 108-113. doi: 10.3969/j.issn.0254-5357.2013.01.019 CHEN Qiang, DIAO Shao-bo, SUN Jian-ye, et al. Measurement of thermal conductivity and saturation of gas hydrates in sediment by thermal pulse probe-time domain reflection technique[J]. Rock and Mineral Analysis, 2013(1): 108-113. (in Chinese) doi: 10.3969/j.issn.0254-5357.2013.01.019
[24]	SUN M Y, SHI B, ZHANG D, et al. Study on calibration model of soil water content based on actively heated fiber-optic FBG method in the in situ test[J]. Measurement, 2020, 165: 108176. doi: 10.1016/j.measurement.2020.108176
[25]	STRIEGL A M, LOHEIDE S P I. Heated distributed temperature sensing for field scale soil moisture monitoring[J]. Groundwater, 2012, 50(3): 340-347. doi: 10.1111/j.1745-6584.2012.00928.x
[26]	CAMPBELL G S, CALISSENDORFF C, WILLIAMS J H. Probe for measuring soil specific heat using A heat-pulse method[J]. Soil Science Society of America Journal, 1991, 55(1): 291-293. doi: 10.2136/sssaj1991.03615995005500010052x
[27]	TARARA J M, HAM J M. Measuring soil water content in the laboratory and field with dual-probe heat-capacity sensors[J]. Agronomy Journal, 1997, 89(4): 535-542. doi: 10.2134/agronj1997.00021962008900040001x
[28]	BRISTOW K, WHITE R, KLUITENBERG G. Comparison of single and dual probes for measuring soil thermal properties with transient heating[J]. Soil Research, 1994, 32(3): 447-464. doi: 10.1071/SR9940447
[29]	BASINGER J M, KLUITENBERG G J, HAM J M, et al. Laboratory evaluation of the dual-probe heat-pulse method for measuring soil water content[J]. Vadose Zone Journal, 2003, 2(3): 389-399. doi: 10.2136/vzj2003.3890
[30]	KNIGHT J H, KLUITENBERG G J. Simplified computational approach for dual-probe heat-pulse method[J]. Soil Science Society of America Journal, 2004, 68(2): 447-449. doi: 10.2136/sssaj2004.4470
[31]	吴冰, 朱鸿鹄, 曹鼎峰, 等. 基于主动加热光纤法的冻土相变温度场特征分析[J]. 工程地质学报, 2019, 27(5): 165-172. https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201905020.htm WU Bing, ZHU Hong-hu, CAO Ding-feng, et al. Investigation of phase change temperature field in frozen soil based on actively heated fiber optics method[J]. Journal of Engineer Geology, 2019, 27(5): 165-172. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GCDZ201905020.htm
[32]	吴冰, 朱鸿鹄, 曹鼎峰, 等. 基于光纤光栅的冻土含冰量监测可行性试验研究[J]. 岩土工程学报, 2019, 41 (12): 2323-2330. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201912025.htm WU Bing, ZHU Hong-hu, CAO Ding-feng, et al. Feasibility study on FBG-based monitoring method for ice content in frozen soil[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(12): 2323-2330. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201912025.htm
[33]	LIU I S. On Fourier's law of heat conduction[J]. Continuum Mechanics and Thermodynamics, 1990, 2(4): 301-305. doi: 10.1007/BF01129123
[34]	DUBI Y, VENTRA M D. Fourier's Law: insight from a simple derivation[J]. Physical Review E, 2009, 79(4): 1-4.

施引文献(7)

期刊类型引用(5)

1.	高磊，袁泽，王勤，高明军. 基于OFDR技术的土体含水率模型研究. 工程地质学报. 2025(01): 96-105 . 百度学术
2.	杨坤，徐卫亚，孟永东，张伟杰，沐清云，蔡征龙. 滑坡地下渗流流速的光纤光栅监测装置研发. 三峡大学学报(自然科学版). 2024(02): 1-7 . 百度学术
3.	叶云雪，易博文，刘小文，吴珺华，洪本根. 脱湿路径下土体水分变化路径及体积变形对滤纸法测定土-水特征曲线的影响. 岩土力学. 2024(08): 2351-2361 . 百度学术
4.	胡优，司炳成，李敏，何海龙，何冬，任姮烨，刘吕刚. 加热光纤法同步测定土壤水热参数误差分析. 土壤学报. 2024(04): 989-997 . 百度学术
5.	朱鸿鹄. 工程地质界面：从多元表征到演化机理. 地质科技通报. 2023(01): 1-19 . 百度学术