Wen Songcheng, Wu Jingwei, Guo Yuan
State Key Laboratory for Tunnel Engineering, School of Civil Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
Sensors (Basel). 2025 Jul 29;25(15):4683. doi: 10.3390/s25154683.
Time domain reflectometry (TDR) has been validated for monitoring water level evolution and riverbed scouring in the laboratory. Previous studies have also validated the feasibility of field-based single hydrological parameter monitoring using TDR. However, the current research focuses on developing separated TDR sensing systems, and integrated measurements of multiple hydrological parameters from a single reflected waveform have not been reported. This study presents an improved helical probe sensor specifically designed for implementation in geologically hard soils, together with an improved data interpreting methodology to simultaneously determine water surface level, bed elevation, and suspended sediment concentration from a single reflection signal. Experimental comparisons were conducted in the laboratory to evaluate the measuring performance between the traditional dual-needle probe and the novel spiral probe under the same scouring conditions. The experiments confirmed the reliability and superior performance of spiral probe in accurately capturing multiple hydrological parameters. The measurement errors for the spiral probe across multiple hydrological parameters were all within ±10%, and the accuracy further improved with increased probe embedding depth in the sand medium. Across all tested parameters, the spiral probe showed enhanced measurement precision with a particularly significant improvement in suspended sediment concentration detection.
时域反射仪（TDR）已在实验室中得到验证，可用于监测水位变化和河床冲刷情况。以往的研究也证实了利用TDR进行现场单一水文参数监测的可行性。然而，目前的研究主要集中在开发单独的TDR传感系统，尚未有关于从单个反射波形中综合测量多个水文参数的报道。本研究提出了一种改进的螺旋探头传感器，专门设计用于在地质坚硬的土壤中应用，同时还提出了一种改进的数据解释方法，可从单个反射信号中同时确定水面高度、河床高程和悬浮泥沙浓度。在实验室中进行了实验比较，以评估在相同冲刷条件下传统双针探头和新型螺旋探头的测量性能。实验证实了螺旋探头在准确获取多个水文参数方面的可靠性和卓越性能。螺旋探头在多个水文参数上的测量误差均在±10%以内，并且随着探头在砂介质中埋深的增加，精度进一步提高。在所有测试参数中，螺旋探头显示出更高的测量精度，在悬浮泥沙浓度检测方面有特别显著的提升。
