What are the primary factors that affect slope stability?

The primary factors affecting slope stability include water and particle cohesion. Water plays a crucial role in slope stability because it can add weight to the materials on a slope, reduce friction between particles, and increase pore water pressure, which may lead to a reduction in effective stress and thus promote failure. When water saturates soil or rock materials, it can lead to increased instability, particularly during heavy rainfall or rapid snowmelt.

Particle cohesion refers to the attractive forces between particles, which can help to keep them bound together. High cohesion increases slope stability, as it resists the forces that push materials downward. Materials with low cohesion are more prone to sliding and erosion, especially when saturated with water. Together, these two factors—water and particle cohesion—significantly influence the overall stability of a slope by ensuring that the forces acting on the slope are balanced in a manner that prevents failure.