To study the stability of spillway side slope of a hydropower station under serious atomized rainfall
the saturated-unsaturated numerical model considering the seepage of the atomized rainfall is conducted to a typical section of slope. The atomized rainfall infiltration induced saturated-unsaturated seepage flow fields is simulated by the finite element method; and base on this
the stability of the slope is evaluated by the unsaturated point safety factor method. The results show that the instability of the slope is mainly caused by the decreasing shear strength
the slowly increasing pressure head and the temporary saturated region
which are induced by the atomized rainfall; The findings can provide reference to the design of slope drainage.