Wang Lichang, Long Wei, Fei Zhanghui, Yang Zhongli, Xu Meng, Wang Lu
School of Geosciences and info-physics, Central South University, Changsha, 410075, China.
Deep Underground Resources and Energy Technology and Innovation Center of Changsha, Changsha, 410083, China.
Sci Rep. 2025 May 9;15(1):16155. doi: 10.1038/s41598-025-98941-w.
Accurate grouting flow measurement is critical for optimizing construction quality and reducing material waste in geotechnical engineering. While electromagnetic flowmeters are widely used, their precision deteriorates significantly under low-flow conditions. This study proposes a laser ranging-based method to address this limitation by analyzing slurry liquid level fluctuations in mixing drums. Through theoretical modeling, indoor experiments, and numerical simulations, the liquid level fluctuation patterns under varying water-cement ratios (0.5:1-5:1) and stirring speeds (40-80 r/min) were investigated. Key findings reveal that liquid level stability increases radially outward from the stirring shaft for ratios ≥ 0.7:1 but inversely for 0.5:1. The slurry surface was categorized into three zones: a turbulent central zone (within 1/3 radius, R/3), a stable intermediate zone (R/3-7R/8), and a high-fluctuation wall zone (7R/8-R). Optimal sensor placement in the stable zone reduced measurement errors to 0.83% (power-function-distributed sensors) and 1.12% (uniformly spaced sensors), significantly outperforming electromagnetic flowmeters (up to 20% error). This work provides a validated framework for sensor layout optimization, enhancing the reliability of laser-based grouting flow detection in practical applications.
精确的灌浆流量测量对于优化岩土工程施工质量和减少材料浪费至关重要。虽然电磁流量计被广泛使用，但在低流量条件下其精度会显著下降。本研究提出了一种基于激光测距的方法，通过分析搅拌桶中浆液液位波动来解决这一局限性。通过理论建模、室内实验和数值模拟，研究了不同水灰比（0.5:1 - 5:1）和搅拌速度（40 - 80转/分钟）下的液位波动模式。主要研究结果表明，对于水灰比≥0.7:1的情况，液位稳定性从搅拌轴径向向外增加，而对于0.5:1的情况则相反。浆液表面分为三个区域：湍流中心区域（半径的1/3以内，R/3）、稳定中间区域（R/3 - 7R/8）和高波动壁面区域（7R/8 - R）。将传感器放置在稳定区域的最佳位置可将测量误差降低至0.83%（幂函数分布传感器）和1.12%（均匀间隔传感器），显著优于电磁流量计（误差高达20%）。这项工作为传感器布局优化提供了一个经过验证的框架，提高了基于激光的灌浆流量检测在实际应用中的可靠性。
