Downward slope: the strike of the main weak structural plane is parallel to or close to the strike of the slope surface and tends to the same slope. When the dip angle of structural plane α is less than the slope angle β, the slope stability is the worst and bedding landslide is easy to occur. This kind of landslide is the most common in nature, and artificial slopes are also easy to be destroyed. When α is greater than β, the slope stability is good.

Anti-slope: the dip angle of the main weak structural plane is opposite to that of the slope, that is, the stratum tends to the slope. This kind of slope is the most stable. Although it sometimes collapses, it is less likely to slide.