Development of Ground Penetrating Radar for Runoff Phenomena

探地雷达已经研制成功并开始销售。这些雷达最初是为了探测地下通信电缆和水管而开发的。一些考古学家利用这些雷达探测埋在地下的遗迹。这些雷达功率低，不符合法律规定。所以，每个人都操作这些雷达。本研究项目旨在探索利用探地雷达提供表层土层的深度、含水率等信息的应用可能性。众所周知，山坡地的径流现象受上述非饱和流方程的支配，而表土层对非饱和流起着重要的作用。如果我们想把这个非饱和流动方程应用到实际中，我们必须准备好这两个关系。一个是rheta（土壤体积占水的比例）和psi（水头）之间的关系。顺序是kappa（毛细管电导率）和rheta之间的关系。其他要求是有关流域的坡长和表层土层的深度。利用探地雷达对在建高尔夫球场表层土壤深度进行了测量，并基于非饱和渗流方程计算了该高尔夫球场的径流量。主要结论总结如下。(1)市场上的探地雷达很难测量土壤中的水分含量。但它们可以探测土壤中的饱和区。(2)可以探测土壤结构。最后，市场上的这些雷达是便携式的，但它们需要AC-100V。这些都很重。如果这些缺陷得到改善，探地雷达将在各个领域得到应用。

Ground penetrating radars have been developed and have been on sale. These radar were originally developed to detect a communication cable and a water pipe underground without excavation. Some archaeologists make use of these radars to probe ruins buried in the ground. These radars are out of a legal regulation because of a low power. So, every operate these radars.This research project aims to seek after the possibility of application of the ground penetrating radar which can provide the information of a surface soil layr such as its depth and moisture content. It is well known that the runoff phenomena at a mountainous slope is governed by the above unsaturated-flow equation and a surface soil layr plays an important role for the unsaturated-flow. If we want to put this unsaturated-flow equation in practice, we have to prepare the two relations. One is a relation ship between rheta (the fraction of the soil bulk volume occupied water) and psi (the hydraulic head). The order is relationship between kappa (the capillary conductivity) and rheta. And the other requirements are the slope length and the depth of surface soil layr for the concerned basin. We measured surface soil depth by using a ground penetrating radar at the golf course under construction and calculated runoff from this golf course based on unsaturated flow equation.The main conclusions are summarized below. (1)It is difficult to measure moisture content in a soil by suing ground penetrating radars on the market. but these can detect saturated zone in a soil. (2)It is possible to probe soil structure.Finally, these radars on the market are portable but these need AC-100V.And these are very heavy. If these defects are improved, earth penetrating radars will be used in various fields.