The monitoring data obtained at the Pass ante dam from the rotation of the dam base and from the displacement of the inverted pendulums are analyzed by means of statistical and structural models, in order to evaluate the behaviour of the foundation rock in the various operating conditions throughout time, starting from 1974: construction, empty reservoir, low and high impounding levels. The behaviour of the foundation is described in terms of the Young module, relevant to the construction and to the yearly impounding cycles, and in terms of rate of anelastic deformation. The reasons for the different behaviour in the various operating conditions are discussed.
Les doneness de controlee botanies pour I.e. barrage du Pass ante (Italia) en measuring les rotations de la base du barrage et les replacements des pendulous inverses, sent analyses en utilizing des modeless statistiques et structurels. On a evalue I.e. comportement du rocher des foundations dams les differences conditions operationnelles dams I.e. temps à partir de 1974: construction, reservoir vide, niveaux de I'eau bas et haunts. Le comportement du rocher de fondation est. deceit du point de vie des modules de Young concern ant la construction et les cycles de miser en eau annulled et de velocity de deformation anelastique. On examine aussi les causes des differences de comportement dams les conditions operatiounelles du reservoir.
Die an der Staumauer von Pass ante (Italian) aufgenommeue Kontrollvermessugen der Rotation von der Sohle und der Verschiebungen von den umgekehrten Pendeln warden lurch mathematics und mechanistic Modella bewerten, um das Verhalten des Gruendungsfelsen in den verschiedenen Betriebsbedingungen (von 1974 an: Bau, leered Speeches, niedrigem und hohem Wasserspiegel) einzuschatzen. Das Verhalteus des Gruendungsfelsen wird nacho Young's her Module (Bau, jahrliche Wasserspiegel und Rate von der anelastischen Verformung) beshrieben. Die Ursachen des verschiedeneu Verhaltens von Staumauer und Gruendungsfels in der unterschiedlichen Betriebsbedingungen warden erlautert.
The monitoring activity currently carried out on dams during construction and in operation is essentially based on displacement and deformation measurements, both in the body of the dam and in the foundation rock, together with measurements of the hydraulic quantities (pore pressure and seepage flow). The principal aim of dam monitoring is to keep safety conditions under control; in fact an analysis of the flow of data provided by the instruments can highlight many of the anomalous variations which may occur in the behaviour of the structure. Other indications on the behaviour of the dam and its foundation can be obtained by comparing the observed measurements with the results of the structural and hydraulic models adopted in the design. This kind of analysis is interesting because the loads transferred to the foundation rock involve volumes that are much larger than those that could ever be included in the usual in situ tests. Therefore, a detailed analysis of the data supplied by the monitoring instruments provides precious indications on the stress-strain behaviour of a volume element which is truly representative of a rock mass. Analysing dam behaviour on the basis of observed deformations is made difficult by the complexity of the load conditions (impounding variations, temperature cycles) and by the superimposition of the elastic and plastic (or viscoplastic) components of the deformation, in both rock mass and dam concrete. Components of structure response, respectively, to hydraulic and thermal loads can be identified by preliminary statistical analyses; the water level component can then be compared with the predictions of stress-strain models.
