Combined Effect of Rainfall and Road on the Stability of Soil Slopes

Slopes are one of the main parts of the environment, which are the habitat of many organisms. Annually, some slopes become unstable due to rainfall, in addition to road rainfall, it can decrease or increase the safety factor of the slope. Stabilizing soil slopes against rainfall is one of the basic challenges discussed in the design and implementation of road construction projects. A parametric study has been used to investigate the combined effect of rainfall and road on the stability of soil slopes using SEEP/W and SLOPE/W software. In this study, first, the effect of rainfall with different intensities on the slope without road was performed. According to the results, depending on the location of the road in the slope, the construction of the road can lead to a decrease or an increase in the initial safety factor in the slope. With the increase in intensity and time of rainfall, the seepage front, water pressure and underground water level increase and the safety factor is decreased. By examining the combined effect of rainfall and road in a case study, it was concluded that the construction of the road on the slope will reduce safety factor more severely during rainfall compared to the case without road. Finding of the present study shows the need to consider the combined effect of road and rainfall during slope stability analysis, which can lead to the reduction of landslides adjacent to the roads.