Is it possible to assess the stability of rock slopes in accordance with the Eurocode?

Abstract

The stability of rock slopes is primarily influenced by discontinuities. An essential requirement for the assessment of stability is therefore structural geological mapping, in which the type (stratification, schistosity, joints, etc.) and spatial orientation of the discontinuities are recorded and documented. The fluctuations of the spatial orientations, which may require the measurement of several hundred interfaces, play an important role here. The current draft of EN 1997-1 points out that the nominal values of the geometric properties of discontinuities can be determined via sensitivity analysis. The sensitivity analysis should be carried out using a probabilistic approach, considering the position, spatial orientation and length of the discontinuities. This general advice is discussed critically and it is shown how a Eurocode-conform assessment of stability could be carried out.