埋地平行铁质管线磁异常模拟与探测识别

磁法管线探测是磁法勘探技术在工程领域的应用拓展,地下铁质管线在地磁场的磁化下会产生磁化场,从而影响原地磁场的分布形成磁异常,通过对探测磁异常信号的采集和解释分析可以进行管线定位。基于麦克斯韦方程组的静磁场理论,利用COMSOL建立了地下平行管线的磁异常正演模型,分析了平行管线不同轴间距、管线长度、管线埋深对探测面和中心测线磁异常分布规律的影响。搭建了可调节导轨、直流减速电机、三轴磁通门传感器、数采与显示器的可移动试验平台,通过平行管试验测量了类似条件下测线的磁异常分布,验证了仿真得到的平行管线磁异常分布的正确性,为磁法非开挖管线的定位研究奠定了基础。

Magnetic Anomaly Simulation and Detection for Buried Parallel Pipelines

Pipeline magnetic anomaly detection is an application development of magnetic exploration technology in the engineering field.Under the magnetization of the geomagnetic field,the underground ferro pipeline will produce a magnetization field and affect the distribution of the original magnetic field to form a magnetic anomaly.Through the signal acquisition,interpretation and analysis of magnetic anomalies,pipeline positioning can be obtained.Based on the static magnetic field theory of Maxwell equations,a magnetic anomaly forward model of parallel pipeline was established by COMSOL,and the effect of different axis spacing,pipeline length,and pipeline burial depth on magnetic anomaly of the detection surface and central detection line was analyzed.A movable test platform with adjustable guide rails,DC reduction motors,three-axis fluxgate sensor,data acquisition and displays component was established.Through parallel pipeline test,the magnetic anomaly distribution of the pipeline was measured under the similar conditions.The test proves that the correctness of numerical simulation for the space distribution of magnetic anomaly field,and it lays a foundation for magnetic trenchless pipeline positioning research.