Identification of elastic stiffness and local stresses in concrete dams by in situ tests and neural networks

In this paper an experimental-numerica! methodology is proposed for the in situ assessment of possibly deteriorated elastic properties of dam concrete and for the estimation of the local stress state in a concrete dam. The methodology described herein consists of the following operative stages: excavation of two parallel small holes (instead of the single one generally employed for rock testing); measurements of diameter variations in both holes by dilatometers; combination of experimental tests with computer simulations and inverse analyses for the parameter identifìcation by means of artifìcial neural networks. Numerica] validation tests of this parameter identification methodology are presented and its novelties and potentialities are discussed.