Analysis of the Influence of Reservoir Water Level Fluctuation on Bank Slope Stability

Abstract

Roads in mountainous areas are always built beside the reservoir. The water level changes when water is stored or discharged, and the change in water level influences slope stability. Based on a certain bank slope project, the influence of water level fluctuation, decreased velocity, soil permeability, and excess pore water pressure on slope stability is analyzed by calculating the flow field and strength reduction of Plaxis. When the soil condition follows a drained behavior, the safety of the slope becomes decrescent and then increscent with the increase or decrease of the reservoir water level. A special water level exists at which the safety factor of slope would be minimal. With the decrease in water level, the safety of the slope following an undrained behavior of the soil would decrease by 10%, in contrast to when the soil follows a drained behavior. The faster the decrease in water level or the smaller the permeability coefficient of the soil, the worse the stability of the slope becomes.