利用探地雷达探测黄河弯道及桥墩周围冰层厚度

摘要

The freezing process of yellow river is a key point in the study of Yellow River ice flood prevention ,detection of the ice thickness around the curve and piers has important significance for prevention of the ice flood .The ground penetrating radar has the advantages of portable ,highly efficient ,continuous ,fast and real time for ice thickness detection .The frequency of the radar antenna determines the penetration depth and resolution of the radar wave .From the radar images ,the air‐water interface and ice‐water interface could be clearly identified .The accuracy of the measurement results was further improved by using ice thick‐ness data from the field drilling to calculate radar propagation velocity in the ice .The measurement results clearly showed that the distribution of ice thickness at the bend and pier was uneven .The ice on the north side of piers and the main channel of the curve was thicker .The ground penetrating radar with 200 Mhz antenna could penetrate the Yellow River ice ,and the radar ima‐ges could clearly show the ice‐water interface .This study could provide the basic data for the analysis of the yellow river ice freezing and melting process and governance of the ice jam in break‐up period .%黄河河道冻结结冰过程是黄河防凌汛研究的一个重点，进行弯道和桥墩周围冰层厚度的探测对防治冰凌灾害具有重要的意义。探地雷达对冰厚探测具有便携、高效、连续、快速、实时等优势。雷达天线的频率决定雷达波的穿透深度和分辨率。从雷达图像上可以清楚的识别空气‐冰界面和冰‐水界面。通过现场打孔测量冰厚数据反算雷达波在冰层中的传播速度进一步提高了测量结果的准确性。测量结果清楚的显示了弯道及桥墩处冰厚分布不均匀。桥墩北侧冰层较厚，弯道主河道处冰层较厚。200 M Hz天线的探地雷达可以穿透黄河冰层，雷达图像可以清楚地显示冰‐水界面。冰层厚度测量为分析黄河冰的冻结、融化过程以及冬春开河期冰塞、冰坝的治理提供了基础数据。