Abstract: In the past studies, the toppling has much research on anti-dip slope while little on the dip slopes, and lots of vacancies exist in the comparisons of the toppling mass formed by the two bedded slopes with different structures. Based on many instances of toppling mass, characteristics of forming condition and development scale about the toppling in dip and anti-dip slope have been studied in detail. The results show that, if the dip slope toppling, it’s usually characterized by the slope height of 100 m, slope angle 35, strata dip angle 60°, and the slope with soft or alternating soft and hard strata that is thin or thin-middle layer structure. With slope angle of 30° and strata dip angle 30°, the anti-dip slope can appear topping-deformation. And its lithology varies from soft to hard with thin to medium thickness layer structure. The concept of “toppling critical dip ” about the layered rock slope is proposed. As for dip slope, the is about 60°. When , the slope can appear the failure of toppling, while , it usually appear the failure of “slide-bending” or “sliding-tension”. The of anti-dip slope is about 30°. Only when can it evolve into obvious toppling; while , the slope won’t dump or dump slightly. As for the two slopes with basically the same geological condition but different slope structures, the distribution area and the toppling depth of toppling mass formed by anti-dip slope are usually greater than that of dip slope, and once the topping formed; the scale of both are usually deep, large or super-large. Besides, the distribution area and the toppling depth of toppling mass present a trend that they increase with the increasing of the slope height. When the slope height is about 250 m, the distribution area and the toppling depth is increase steeply, and the increasing amplitude of anti-dip slope is greater than that of dip slope.

Key words: steep stratified rock slope, toppling-deformation, formation conditions, characteristics of development scale