Model Test of Deformation Evolution and Multi Factor Prediction of Anchorage Slope Stability under Rainfall Condition

The stability of the anchorage slope on the Baiyang Yangtze River Highway Bridge in Yichang, China, was investigated under different rainfall conditions using model test, numerical simulation, and factor analysis. The results of the study are as follows: (1) with the increase of rainfall intensity, the change of earth pressure can be divided into three stages. However, when the rainfall intensity was larger than a certain value, the change of earth pressure of cut slope became two stages; with the increase of rainfall intensity, pore water pressure increased with the increase of rainfall time, while at a certain stage after the rainfall, the pore water pressure in the cut slope did not decrease immediately, but increased for a period of time. (2) When the rainfall stopped, the stability coefficient of the anchorage slope continued to decrease, then slowly increased, and finally tended to be gentle. Meanwhile, when the rainstorm reached a certain intensity, the main factor that restricted the rainfall infiltration rate became the geotechnical permeability coefficient of the cut slope, which was no longer the rainfall intensity. (3) Factor analysis shows that the rainfall intensity and rainfall duration were the most important factors for anchorage slope stability, while earth pressure, pore water pressure and slope displacement were much less significant.