SEEPAGE CHARACTERISTICS AND STABILITY ANALYSIS OF RESERVOIR BANK SLOPE UNDER COMBINED ACTION OF RAINFALL AND RESERVOIR WATER LEVEL FLUCTUATION

Based on the theory of saturated-unsaturated seepage, the effects of the combined action of rainfall and water level fluctuation on the pore water pressure of soil in bank slope and the law of deep and shallow landslides stability are investigated by using the finite element software. The results show that no rainfall occurs during the change of reservoir water level, the farther the monitoring point is from the reservoir water level, the smaller the change of pore water pressure is after the reservoir water level ceases to fluctuate. When rainfall occurs in the process of reservoir water level changing, the pore pressure of monitoring point will suddenly increase, and will decrease slowly after the rain stops. When rainfall occurs during reservoir draw-down, the factor of safety will suddenly decrease, and after the rain stops, the factor of safety will gradually increase. In a word, landslides induced by the combined action of rainfall and water level fluctuation would pose a threat to its neighboring eco-environment.