Analysis on water damage mechanism and influencing factors of embankment slope under rainfall

In order to clarify the influence of rainfall on the seepage field and stability of embankment slope,the mechanism of embankment slope water failure and its main influencing factors were studied.Under the specific control conditions of soil quality,compaction degree and erosion infiltration time,this study explored the erosion damage of subgrade slope under rainfall through slope model test,and then combined with GeoStudio program to find out the seepage field and stability change law of subgrade slope during rainfall.The results show that in the process of rainfall,the slope surface is scoured by rain water and the external structure is damaged,while the internal stability of the slope is reduced by the seepage action of rain water.The two effects from the outside to the inside simultaneously lead to the overall damage of the slope.With the increase of compaction degree of two kinds of soil slopes from 85% to 95%,the erosion amount of sandy soil slopes decreased by 4618%,and the slope safety factor increased by 1374%,while the erosion amount of cohesive soil slopes decreased by 3370%,and the safety factor increased by 1021%.With the increase of rainfall time,the scouring depth of cohesive soil slope tends to be stable in the later stage,while the scouring depth of sandy soil slope tends to increase; Under the same control conditions,the change of safety factor of cohesive soil slope before and after rainfall is smaller than that of sandy soil slope.Under the same control conditions,the water damage resistance and overall stability of the clay soil slope are stronger than that of the sandy soil slope.The research results are helpful for more comprehensive understanding of the water-damage mechanism of the embankment slope and the influence laws of the main factors in the process of rainfall,and improve the stability of the road support