| Spatial evaluation of the water infiltration characteristics in the vadose zone is one of the important issues to assess the safety of levee and road embankment. In order to delineate the infiltration front, we conducted resistivity monitoring by means of a high speed resistivity measurement tool at a small model levee. The tool can acquire and store a total of 576 V/I responses within only 30 seconds. A survey line was set at across the model levee. A small trench was dug on the crown and water was poured into the trench. We monitored water infiltration process under constant water level at 5 minutes interval. After stopping the water pouring, we monitored diffusion process at 30 minutes intervals. Fortunately, we could monitor water infiltration process accompanied by a rainfall, the total precipitation of which was 30 millimeters in a day. As a result, extension of the wetting front was clearly imaged as a relatively resistivity change body. Resistivity monitoring by using high speed resistivity measurement tool was effective to image detailed water infiltration process, and had a possibility of evaluating the characteristics of unsaturated hydraulic property in the field. |
