Development and Test of Multi-Level Fiber Bragg Grating Temperature and Water Pressure Sensing System in the Bor [孔內多深度光纖光柵水壓與溫度感測系統研發與測試]

Abstract

Groundwater are the main source of water supply in the semi-arid or arid areas. If the aquifers are contaminated, it will immediately affect people's health. Meanwhile, groundwater rehabilitation will also face great challenges. To predict the movement path of the remediation agent and the plume in the aquifer, it is very important to observe the aquifer status, such as water quality, water pressure, temperature, etc. However, the traditional EPA monitoring well always opens screen at a specific depth range and can only measure the average aquifer status, which can provide limited information for groundwater delineation. To address this issue, we employ fiber Bragg grating (FBG) technology to develop a multi-level groundwater pressure and temperature sensing system, which can simultaneously measure multiple water pressures and temperatures at different depths in the same borehole. This system takes the advantage of optical fiber: long-distance and stable signal transmission, the signal is not easily interfered by water and electromagnetic waves, and no sparks. To demonstrate the capability of the developed multi-depth discrete FBG sensing system, we have conducted an indoor test and an on-site test, and the results are discussed in this study. ? 2021, Chinese Institute of Civil and Hydraulic Engineering. All right reserved.