Abstract:

In order to discuss the influence of rainfall infiltration on the stability of granite terrace slope, this paper takes the Ziquejie terrace in Hunan Province as an example. Based on the analysis of the geological conditions of Ziquejie terrace, the seepage field and stability of different slope gradients and different  soil layer thicknesses under rainstorm conditions were analyzed based on the coupling of multiple modules of the finite element numerical simulation software Geostudio. The results show that under the working condition of 90 mm/d rainfall intensity and 5 days  rainfall duration, the slopes with 35° and 40° gradients are in a state of destabilization, and the stability coefficient is negatively correlated with the increase of slope gradient; The thicker the fully weathered soil layer is, the lower the safety factor of the slope is. After 5 days of rainfall, the stability coefficients of different soil layers under different working conditions are similar. However, when there is no rainfall, the thinner the fully weathered soil layer is, the more stable the slope is.

Key words: Ziquejie terrace, granite, rainfall infiltration, slope stability, gradient, soil layer thikness