This paper contains the results of the back analysis performed after the earthquake of April 2009 (L'Aquila Central Italy) on the Rio Fucino gravity dam
(reservoir of Campotosto, L’Aquila).
The elaboration of the back analysis made it possible to estimate the shear strength at the contact surface between the dam and the rock foundation and the strength of rock foundation itself, both simulated by Mohr-Coulomb’s criteria.
The dam-rock contact results have been compared with the values of technical literature.
Moreover, the back analysis permitted the definition of the lower limit strength of the rock foundation and the valuation of the actual dam safety conditions under maximum credible earthquake (MCE).