Abstract
Since seventy percent of countries are mountain ranges in Japan, and there is also much rain, the present condition is that landslides have occurred in many domestic areas. In such a slope disaster, when carrying out design construction of the preventive measures, it is necessary to grasp the geological structure of an object area. Generally, it is mainly investigated by the drilling survey which is able to check a stratum certainly. However, if it is going to hold the geological condition of the whole foundation which a landslide has produced, many drilling surveys are required, and it takes much cost and time. From the former, exploration tools, such as elastic wave exploration and resistivity tomography, are applied. However, development of more compact and simple investigation system is made into pressing need.
In this research, in order to measure the low resistivity layer in near a landslide side, a compact measurement machine is developed, and its precision for measurement was checked at the actual site by comparison with drilling surveys. This machine is improved from electromagnetic method with separate coil to electromagnetic method with coaxial coil based on central induction method. Moreover, the applicability of the method in real ground was examined.
