INFLUENCE OF RAINFALL INTENSITY ON INFILTRATION SURFACE FORMATION OF RIVER EMBANKMENTS

Abstract

In recent years, a local downpour occurs frequently in various parts of Japan and there is an embankment destroyed by the downpour. River embankments are important structures to protect residents from floods and other disasters. Many long embankments are historical products of flood control that have been reinforced by raising them with age. However, the structure of the river embankment was developed based on the experience of the disaster that occurred, and the design and analysis of the destruction of the structure were not analyzed. Furthermore, up to now, the mechanism of the levee collapse has been discussed, and it has not been fully elucidated. In this study, we perform a numerical analysis considering the infiltration boundary of the slope of the embankment and express the difference in stress behavior in the embankment before and after considering the infiltration boundary. We analyzed the stress behavior of the embankment when the river water level rises by analysis and tried to analyze the collapse mechanism of the river embankment by analyzing the effect. In addition, we observed the stress behavior when precipitation was applied and performed a detailed analysis closer to the actual problem. Also, it was analytically confirmed that the fracture mode of the embankment differs depending on the presence or absence of the infiltration boundary. At that time, it was analytically confirmed that the failure mode of the embankment was different depending on the difference in the water level rising speed.