输水管道异常振动的分布式光纤声监测定位方法研究  

Research on localization method for distributed acoustic m onitoring of abnormal vibrations in w ater pipeline

作　　者：韦昊南 商峰[1] 刘毅[1] 王亦斌 刘乔木 陈东 WEI Haonan;SHANG Feng;LIU Yi;WANG Yibin;LIU Qiaomu;CHEN Dong(China Institute of Water Resources and Hydropower Research,Beijing 100038,China;China South-to-North Water Diversion Corporation Limited,Beijing 100142,China)

机构地区：[1]中国水利水电科学研究院,北京100038 [2]中国南水北调集团水网水务投资有限公司,北京100142

出　　处：《中国水利水电科学研究院学报(中英文)》2025年第2期184-193,共10页Journal of China Institute of Water Resources and Hydropower Research

基　　金：国家重点研发计划项目(2018YFC0406903);水利部小基建项目(SSJJXM02272201);中国水利水电科学研究院科研专项(SS0145C042023);PCCP断丝监测科研项目(SS120203A0072024)。

摘　　要：分布式光纤声传感技术(DAS)可用于监测输水管道沿程发生的施工破坏、断丝等异常振动事件。然而,该技术在长距离条件下的应用受多个因素限制,且定位精度较低。本文将连续的传感光缆视为点式传感阵列,并应用短时傅里叶变换提出了基于到达时差的异常振动定位方法。通过开展原型管道的敲击试验,分析不同类型敲击振动信号传播特征,并对波速和到达时间选取准则对定位误差的影响进行了敏感性分析。结果表明,采用固定阈值的方式得到的定位结果,随选取计算波速的增大,整体偏向敲击位置所在通道的中点;对于混凝土回弹仪的敲击,采用极大值及其比例的方式得到的定位结果整体远离敲击位置所在通道的中点。在选择更小的阈值和波速作为计算参数时,所得定位误差较小,误差范围最小可达±0.1 m,标准差最小为0.09 m。该方法以较大的系统空间分辨率得到了较小的定位误差,为DAS技术在实际工程中的推广应用提供参考。Distributed Acoustic Sensing(DAS)can be used to monitor abnormal vibration events,such as construction damages and wire break along water pipelines.However,its application under long-distance conditions is limited by multiple factors,and its positioning accuracy is relatively low.This paper treats the continuous sensing fiber optic cables as a point-type sensing array,and proposes an abnormal vibration localization method based on time-delay of arrival using the short-time Fourier transform.By conducting impact tests on prototype pipelines,this study analyzes the propagation characteristics of vibration signals from different types of impacts,and performs a sensitivity analysis on the influence of wave speed and arrival time selection criteria on localization error.The results indicate that when using a fixed threshold method,the localization results tend to shift towards the midpoint of the channel where the impact occurs as the calculated wave speed increases.In contrast,for the impact test with the concrete rebound hammer,the localization results obtained by using the peak value and its ratio tend to shift away from the midpoint of the channel where the impact occurs.Smaller localization errors can be achieved when smaller threshold values and wave speeds are chosen as calculation parameters.The error range can be as small as±0.1 m,with a minimum standard deviation of 0.09 m.This method achieves small positioning errors with a relatively large system spatial resolution,providing valuable insights for the practical application of DAS technology in engineering projects.

关 键 词：输水管道 分布式光纤声传感 异常振动 时频分析 定位方法 

分 类 号：TV698.1[水利工程—水利水电工程]