The control of slope angle and slope height in identifying stability condition of slopes is a ready reckoner for fast screening of slopes covered with soil and debris material. The heterogeneity of the material in the slope though plays a major role, however, understanding the behaviour of the homogenous material throws light on generic principle of stability and types of failure. The present study therefore intends to derive the relationships of the safety factor of a homogeneous material that is only subjected to self-weight in three dimensions. The bearing of slope geometry on the safety factor of a predefined homogeneous slope is analysed in 3D following the finite element-based strength reduction technique for establishing the relationships and the resultant failure modes. The type of failure and shape of the sliding mass is found guided by the slope geometry. The results indicate that FOS decreases nonlinearly with increasing height but decreases linearly with increasing slope angle. The findings indicate that the height and angle of the slope control the failure process of a particular “material type” and the expected type of failure. The 3D finite element method (FEM) with strength reduction (SRM) is a reliable approach for analyzing high and steep slopes, as it effectively captures complex, non-circular failures and progressive instability by reducing shear strength parameters. This insight can guide practicing professionals from making informed designs on geometry alteration of slopes for effective stabilization.
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