上覆地层及管内充物对非金属管线探测的影响

The Impact of Overlying Strata and Tube Filling on the Non-Metallic Pipeline Detection

通过一系列的实验,分析和讨论了不同上覆地层和管线内部充填物对非金属管线探测结果的影响规律。研究表明:不同地层下雷达天线耦合作用存在差异,在粘土中耦合的雷达波中心频率和频带宽度相比砂土更低;不同地层中雷达子波传播有所不同,在砂土中雷达反射波的中心频率降低和频带宽度都随深度而降低,粘土中的中心频率无明显变化,频带宽度显著变窄;因此在砂土中非金属管线的探测结果的准确性比粘土中的高。非金属管线内部充填物对非金属管线的探测准确性有较大影响,在上覆砂土的情况下,管内充填水、湿砂时的管线探测准确性比管内无充填的高。

Through a series of experiments, this paper gives some analysis and discussions of the impact of different overlying strata and tube filling on the non-metallic pipeline detection. The study shows that the coupling of radar antenna with the ground surface is different under different subsurface. When coupling with the clay , the center frequency and bandwidth of the antenna radiation drop lower than that coupling with the sand. The radar radiation is different in different strata, the center frequency and bandwidth of the radiation drops with the depth in the sand, while the center frequency changes little and the bandwidth drop significantly in the clay. Therefore, the accuracy of the non-metallic pipeline detection is higher in the sand than in the clay. It is found that the tube internal filler has a significant impact on the detection accuracy of the non-metallic pipeline, when overlaid with sand, the accuracy of pipeline detection was better when tube filled with wet sand or water than that with no filler.