基于磁梯度法的地下深埋管线探测方法研究

Research on Detection Method of Deep Buried Pipeline Based on Magnetic Gradient Method

摘要:

随着城市建设发展，有大量的管线采用非开挖技艺进行敷设，管线埋置越来越深，常规物探方法将很难满足实际探测工作的需要。目前，井中磁梯度法是深埋管线常用的探测方法之一，主要用来探测深埋金属管线。但是实际工程中，往往仅凭借出现磁梯度异常和极值异常等的定性判断，缺少对深埋管线定量分析的方法。通过数据模拟和工程实例相结合的方法，对地下深埋金属管线的井中磁梯度探测问题展开了深入探索。通过对模型正演数据的曲线拟合确定了有效磁化倾角、钻孔与管线的水平距离、管线埋深与模拟的磁梯度值及其对应深度的拟合关系式，用此关系式进行管线水平位置和埋深的估算，达到对目标管线进行定量分析的目的，并结合工程实例，证明了估算公式的可行性。

Abstract:

With the development of urban construction, a large number of pipelines are laid by using trenchless techniques, and pipelines are buried deeper and deeper. Conventional geophysical prospecting methods will be difficult to meet the needs of actual detection work. At present, the borehole magnetic gradient method is one of the commonly used detection methods for deep-buried pipelines. It is mainly used to detect the deep-buried metal pipelines. However, in actual engineering, the quantitative analysis method of deep buried pipeline is often lack only by the quantitative judgment of magnetic gradient anomaly and extreme value anomaly. Through a combination of data simulation and engineering examples, an in-depth exploration of the problem of borehole magnetic gradient detection for underground metal pipelines is carried out. Through the curve fitting of the model forward data, the fitting relationship between the effective magnetization inclination, the horizontal distance between the borehole and the pipeline, the pipeline buried depth and the simulated magnetic gradient value and its corresponding depth is determined. This relationship is used to estimate the level position and burial depth of the pipeline in order to achieve the quantitative analysis of the target pipeline. And combined with the engineering examples, the feasibility of the estimation formula is proved.