Abstract: The stability of bedding rock slope is mainly affected by the physico-mechanical properties of slide face and the groundwater pressures on slope rock. On the basis of analysing the groundwater pressure, we established the hydrostatic pressure model of rock bedded slope in two cases (blocked outflow seam and unblocked outflow seam). Subsequently we derived the formulas for calculating slope stability coefficient and critical water height in separation fracture, and put forward the criterion for bedding-slip failure of rock slope. According to the criterion, slope will lose its stability once the water height of separation fracture or the critical rainfall intensity reaches a critical value. Calculation example verified the rationality of the proposed formulas. Results also reveal that the decrease in slope stability under the influence of groundwater is mainly related to hydrostatic pressure and uplift force instead of groundwater penetration. The results provide important guide for engineering design and construction.

Key words: slope engineering, rock slope, gently inclined bedded, hydraulic pressure, stability