The rock slope stability assessment can be performed by means of deterministic and
probabilistic approaches. As the deterministic analysis needs only representative values (generally,
the mean value) for each physical and geo-mechanical parameter involved, it does not take into
account the variability and uncertainty of geo-structural and geo-mechanical properties of joints. This
analysis can be usually carried out using dierent methods, such as the Limit Equilibrium method or
numerical modeling techniques sometimes implemented in graphical tests to identify dierent failure
mechanisms (kinematic approach). Probabilistic methods (kinetic approach) aimed to calculate the
slope failure probability, consider all orientations, physical characters and shear strength of joints
and not only those recognized as kinematically possible. Consequently, the failure probability can
be overestimated. It is, therefore, considered more realistic to perform both kinematic and kinetic
analyses and to calculate a conditional probability given by the product of the kinematic and kinetic
probabilities assuming that they are statistically independent variables. These approaches have been
tested on two rock slopes in the Campanian region of Southern Italy aected by possible plane and
wedge failures, respectively. Kinematic and kinetic probabilities have been evaluated both by means
of the Markland’s test and the Monte Carlo simulation. Using the Eurocode 7, also a deterministic
limit equilibrium analysis was performed. The obtained results were compared and commented on