Characterization of Soil Moisture Distribution and Movement Under the Influence of Watering-Dewatering Using AHFO and BOTDA Technologies

Ding-Feng Cao, Bin Shi, Hong-Hu Zhu, Chao-Sheng Tang, Zhan-Pu Song, Guang-Qing Wei, Ankit Garg

Environmental and Engineering Geoscience (2018) 1-14.

Abstract: The infiltration and distribution of water through unsaturated soil determine its mechanical and hydrological properties. However, there are few methods that can accurately capture the spatial distribution of moisture inside soil. This study aims to demonstrate the use of actively heated fiber optic (AHFO) and Brillouin optical time domain analysis (BOTDA) technologies for monitoring soil moisture distribution as well as strain distribution. In addition to a laboratory model test, finite element analyses were conducted to interpret the measurements. During the experiment, the fine particle migration was also measured to understand its influence on soil hydraulic conductivity. The results of the experiment indicate that (i) for a soil that has never experienced a watering-dewatering cycle, water infiltration can be accurately calculated using the Richards’ equation; (ii) migration of fine soil particles caused by the watering-dewatering cycle significantly increases the hydraulic conductivity; and (iii) two critical zones (drainage and erosion) play significant roles in determining the overall hydraulic conductivity of the entire soil. This study provides a new method for monitoring the changes in soil moisture, soil strain, and hydraulic conductivity. The observations suggest that the effect of fine particles migration should be considered while evaluating soil moisture distribution and water movement.

Keywords: Soil Moisture, Distributed Monitoring, Richards’ Equation, Fiber Optic Sensor, Fine Particles


AHFIR, N. D.; BENAMAR, A.; ALEM, A.; AND WANG, H. Q., 2009, Influence of internal structure and medium length on transport and deposition of suspended particles: a laboratory study. Transport in Porous Media, Vol. 76, No. 2, pp. 289.

AN N.; HEMMATI S.; CUI Y.J.; MAISONNAVE C.; CHARLES I.; TANG C. S.; 2018, Numerical analysis of hydro-thermal behavior of Rouen embankment under climate effect. 2017. Computers and Geotechnics, Vol. 99, pp. 137-148.

BARBOUR, S. L.; HENDRY, M. J.; AND CAREY, S. K., 2016, High-resolution profiling of the stable isotopes of water in unsaturated coal waste rock: Journal of Hydrology, Vol. 534, pp. 616-629.

BENAMAR, A.; AHMED, N. D.; WANG, H. Q.; AND ALEM, A., 2008, Particle transport in a saturated porous medium: Pore structure effects: Comptes rendus – Géoscience, Vol. 339, No.10, pp. 674-681.

BENÍTEZ-BUELGA, J.; SAYDE, C.; RODRÍGUEZ-SINOBAS, L.; AND SELKER, J. S, 2014, Heated fiber optic distributed temperature sensing: A dual-probe heat-pulse approach: Vadose Zone Journal, Vol. 13, No. 11, pp. 1-12.

BENÍTEZ‐BUELGA, J.; RODRÍGUEZ‐SINOBAS, L.; CALVO, S. R.; GIL‐RODRÍGUEZ, M.; SAYDE, C.; AND SELKER, J. S., 2016, Calibration of soil moisture sensing with subsurface heated fiber optics using numerical simulation: Water Resources Research, Vol. 52, No. 4, pp. 2985-2995.

BENSE, V. F.; READ, T.; BOUR, O.; LE BORGNE, T.; COLEMAN, T.; KRAUSE, S.; CHALARI, A.; MONDANOS, M.; CIOCCA, F.; AND SELKER, J. S., 2016, Distributed Temperature Sensing as a downhole tool in hydrogeology: Water Resources Research, Vol. 52, No. 12, pp. 9259-9273.

BROOKS, R. H.; AND COREY, A. T., 1964, Hydraulic properties of porous media and their relation to drainage design: Transactions of the ASAE, Vol. 7, No. 1, pp. 26-28.

CAO, D. F.; SHI, B.; WEI G. Q.; CHEN S. E.; AND ZHU, H. H., 2018, An improved distributed sensing method for monitoring soil moisture profile using heated carbon fibers: Measurement, Vol. 123, pp. 175-184.

CAO, D. F.; SHI, B.; ZHU, H. H.; WEI G. Q.; CHEN S. E.; AND YAN J. F., 2015, A distributed measurement method for in-situ soil moisture content by using carbon-fiber heated cable: Journal of Rock Mechanics and Geotechnical Engineering, Vol. 7, No. 6, pp. 700-707.

CAO, D. F.; SHI, B.; ZHU, H. H.; ZHU, K.; WEI G. Q.; AND GU K., 2016, Performance evaluation of two types of heated cables for distributed temperature sensing-based measurement of soil moisture content: Journal of Rock Mechanics and Geotechnical Engineering, Vol. 8, No. 2, pp. 212-217.

CARSLAW, H. S.; AND JAEGER, J. C., 1959, Conduction of heat in solids. Oxford: Clarendon Press, 2nd ed.

CARSEL, R. F.; AND PARRISH, R. S., 1988, Developing joint probability distributions of soil water retention characteristics: Water Resources Research, Vol. 24, No. 5, pp. 755-769.

CHETTI, A.; BENAMAR, A.; AND HAZZAB, A., 2016, Modeling of particle migration in porous media: application to soil suffusion: Transport in Porous Media, Vol. 113, No. 3, pp. 1-16.

FLORIDES, G.; AND KALOGIROU, S., 2008, First in situ determination of the thermal performance of a U-pipe borehole heat exchanger, in Cyprus: Applied Thermal Engineering, Vol. 28, No. 2, pp. 157-163.

GIL-RODRÍGUEZ, M.; RODRÍGUEZ-SINOBAS, L.; BENÍTEZ-BUELGA, J.; AND SÁNCHEZ-CALVO, R., 2013, Application of active heat pulse method with fiber optic temperature sensing for estimation of wetting bulbs and water distribution in drip emitters: Agricultural Water Management, Vol. 120, pp. 72-78.

HARDY, R. A.; JAMES, M. R.; PATES, J. M.; AND QUINTON, J. N., 2017, Using real time particle tracking to understand soil particle movements during rainfall events: Catena, Vol. 150, pp. 32-38.

Hayek, M., 2015, An analytical model for steady vertical flux through unsaturated soils with special hydraulic properties: Journal of Hydrology, Vol. 527, pp. 1153-1160.

HERRADA, M. A.; GUTIÉRREZ-MARTIN, A.; AND MONTANERO, J. M., 2014. Modeling infiltration rates in a saturated/unsaturated soil under the free draining condition. Journal of Hydrology, Vol. 515, pp. 10-15.

HORIGUCHI, H.; AND TATEDA M, 1989, BOTDA-nondestructive measurement of single-mode optical fiber attenuation characteristics using Brillouin interaction: theory. Journal of Lightwave Technology Vol. 7, No. 8, pp. 1170-1176.

HORIGUCHI, T.; SHIMIZU, K.; KURASHIMA, T.; TATEDA, M.; AND KOYAMADA, Y., 1995, Development of a distributed sensing technique using Brillouin scattering: Journal of Lightwave Technology, Vol. 13, No. 7, pp. 1296-1302.

LAI, W. L.; KOU, S. C.; AND POON, C. S., 2012, Unsaturated zone characterization in soil through transient wetting and drying using GPR joint time–frequency analysis and grayscale images: Journal of Hydrology, Vol. 452, pp. 1-13.

LIU, S.; AND YEH, T. C. J., 2004, An integrative approach for monitoring water movement in the vadose zone: Vadose Zone Journal, Vol. 3, No. 2, pp. 681-692.

LU, N.; AND GODT, J. W, 2013, Hillslope hydrology and stability, Cambridge University Press, pp. 91.

MATHIAS, S. A.; AND BUTLER, A. P., 2006, Linearized Richards' equation approach to pumping test analysis in compressible aquifers: Water Resources Research, Vol. 42, No. 6, pp. W06408.

MINARDO A.; CATALANO E.; MOLLO L.; CRECO R.; AND ZENI L., 2016, Moisture Measurement in Masonry Materials Using Active Distributed Optical Fiber Sensors: Sensors, Vol. 431, pp. 149-154

NIU, Q.; FRATTA, D.; AND WANG, Y. H., 2015, The use of electrical conductivity measurements in the prediction of hydraulic conductivity of unsaturated soils: Journal of Hydrology, Vol. 522, pp. 475-487.

ROGERS, J. D.; AHMED M F.; ISMAIL E. H., 2016, Landslide susceptibility screening using wind-driven rainfall: Environmental & Engineering Geoscience, Vol. 22, No. 2, pp. 1-22.

SAYDE, C.; BUELGA, J. B.; RODRIGUEZ‐SINOBAS, L.; KHOURY, L.; ENGLISH, M.; VAN DE GIESEN, N.; AND SELKER, J. S., 2014, Mapping variability of soil water content and flux across 1–1000 m scales using the actively heated fiber optic method: Water Resources Research, Vol. 50, No. 9, pp. 7302-7317.

SAYDE, C.; GREGORY, C.; GIL‐RODRIGUEZ, M.; TUFILLARO, N.; TYLER, S.; VAN DE GIESEN, N.; ENGLISH, M.; CUENCA, R.; AND SELKER, J. S., 2010, Feasibility of soil moisture monitoring with heated fiber optics: Water Resources Research, Vol. 46, No. 6, pp. 2840-2849.

SONG, Z.; SHI, B.; JUANG, H.; SHEN, M.; AND ZHU, H., 2016, Soil strain-field and stability analysis of cut slope based on optical fiber measurement: Bulletin of Engineering Geology and the Environment, Vol. 76, No. 3, pp. 937-946.

STRIEGL, A. M.; AND LOHEIDE, P. S., 2012, Heated distributed temperature sensing for field scale soil moisture monitoring: Groundwater, Vol. 50, No. 3, pp. 340-347.

SOURBEER, J. J.; AND LOHEIDE, S. P., 2016, Obstacles to long‐term soil moisture monitoring with heated distributed temperature sensing: Hydrological Processes, Vol. 30, No. 7, pp. 1017-1035.

SU, H.; TIAN, S.; KANG, Y.; XIE, W.; AND CHEN, J., 2017, Monitoring water seepage velocity in dikes using distributed optical fiber temperature sensors: Automation in Construction, Vol. 76, pp. 71-84.

SUN, H., 2016, A semi-analytical solution for slug tests in an unconfined aquifer considering unsaturated flow: Journal of Hydrology, Vol. 532, pp. 29-36.

TANG C. S.; WANG D.Y.; ZHU C.; ZHOU Q. Y.; XU S. K.; ADD SHI B., 2018, Characterizing drying-induced clayey soil desiccation cracking process using electrical resistivity method: Applied Clay Science, Vol. 152, pp. 101-112.

TORAN, L., AND JEDRZEJCZYK, C., 2017, Water level monitoring to assess the effectiveness of stormwater infiltration trenches: Environmental & Engineering Geoscience, Vol. 23, No. 2, pp. 1078-7275.

VAN GENUCHTEN, M.T., 1980, A closed-form equation for predicting the hydraulic conductivity of unsaturated soils: Soil Science Society of America Journal, Vol. 44, No. 5, pp. 892-898.

WANG L. L.; TANG C. S., SHI B., CUI Y., ZHANG G. Q., HILARY I., Nucleation and propagation mechanisms of soil desiccation cracks. Engineering Geology, Vol. 238, pp. 27-35.

WEILL, S.; FREDERICK D.; YI, P.; AND PHILIPPE A., 2017, A low-dimensional subsurface model for saturated and unsaturated flow processes: ability to address heterogeneity: Computational Geosciences, Vol. 21, No. 2, pp. 301-314.

WU, J. H.; SHI, B.; CAO, D. F.; JIANG, H. T.; WANG, X. F.; AND KAI, G., 2017, Model test of soil deformation response to draining-recharging conditions based on DFOS: Engineering Geology, Vol. 226, pp. 107-121.

YAN, J. F.; SHI, B.; ZHU, H. H.; WANG, B. J.; WEI, G. Q., AND CAO, D. F., 2015, A quantitative monitoring technology for seepage in slopes using DTS: Engineering Geology, Vol. 186, pp. 100-104.

ZHU, Y.; SHI, L. S; LIN, L.; YANG, J. Z.; AND YE, M., 2012, A fully coupled numerical modeling for regional unsaturated–saturated water flow: Journal of Hydrology, Vol. 475, pp. 188-203.