Earthquake resistance of the Nurek dam

Concerning the problem of the seismic stability of the Nurek dam

“…In accordance with the technique proposed by Gidroproekt [7] for calculating the earthquake resistance of the Nurek dam by wave dynamics methods (WDMS) to "seismic actions of low probability," corresponding approximately to a frequency of once in i0,000 years, an accelerogram with a peak acceleration of i.i g recorded on a rock projection of a canyon near the left-bank abutment of the Pokoima arch dam during the 1971 San Fernando earthquake (California, USA) with M = 6.6 was selected.…”

“…The authors of [6,7] conducted investigations to select "seismic actions of low probability," to determine the strength (shear strength) of the gravel-pebble materials of the dam shoulders, including on the basis of the data of large-scale tests, and also to select the designs and layout of antiseismic collars and evaluate the seismic stability of a reinforced dam.…”

“…The final part of [7] is devoted to a description of the design and layout of the antiseismic collars and to an evaluation of the eqrthquake resistance of the Nurek dam reinforced by the collars with an indication of the technical and economic effect achieved in this case.…”

“…The suggestion of reinforcing the Nurek dam with reinforced-concrete antiseismic collars was made for the first time by the authors of [7], who proposed a "discrete" reinforcement variant. The suggestion of reinforcing the Nurek dam with reinforced-concrete antiseismic collars was made for the first time by the authors of [7], who proposed a "discrete" reinforcement variant.…”

“…The suggestion of reinforcing the Nurek dam with reinforced-concrete antiseismic collars was made for the first time by the authors of [7], who proposed a "discrete" reinforcement variant. Yet the authors of [7] selected the dimensions and sites of the antiseismic collars in the structure on the basis of the data of quite similified calculations of an unreinforced dam: within the scope of the standard linear sepctral theory with the use of diagrams of the "deficit" of resisting forces (or their moments) for the most dangerous sliding wedges determined by checking the seismic stability of the slopes by the usual methods; by wave dynamics methods for the action assigned by the accelerogram of the 1971Pokoima earthquake with a peak acceleration of I.i g with the use for soil of the model of a perfectly elastoplastic body with a Prager-Drucker associated law of plasticity. The lower collar is embedded 65 m into the dam body.…”