物理探査による堤防内部の浸潤過程の可視化

抄録

Infiltration process in a levee was monitored by resistivity and MASW (Multichannel Analysis of surface waves) survey. The levee consisted of gravelly soil and was covered with cohesive soil. The experiment was carried out during the rise of water level on the riverside. As a result, resistivity survey could delineate water movement from riverside to landside in the levee body. Meanwhile, MASW survey could delineate the area of decreasing of shear wave velocity due to release of insitu stress and decreasing of stiffness which was caused by increasing of volumetric water content. In conclusion, time lapse resistivity survey was useful to image infiltration process in the levee. In addition, time lapse MASW survey could assess the change of stability of the levee. Monitoring by means of geophysical survey was effective to characterize dynamic response in the levee.