Conclusions
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1.
The results of theoretical and experimental investigations and data from full-scale observations indicate that even in the case of sufficiently high safety factors in dams and absence of tensile stresses in the concrete-rock interface, a zone of tensile stresses below the interface is almost always developed, which at some dams leads to damage of the impervious curtains and to other adverse phenomena capable of disturbing the normal operation of the structure and sometimes causing failure.
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2.
It is necessary to introduce into the design methods of analysis and investigation of the stress-strain conditions of rock masses below the lower surface of dams, in order to establish the zones of tensile and larger comptessive stresses.
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3.
The analyses and investigations carried out reveal that it is practically impossible to prevent tensile stresses in the foundations of concrete dams. However, it is evidently unnecessary to prevent these stresses. The overwhelming majority of dams are being successfully operated under these conditions. Nevertheless, our knowledge about the operating conditions of foundations without analyses of their stress conditions is insufficient. Such analyses are necessary in order to develop constructional measures which, by taking into account the specific geologic conditions, will ensure normal operating conditions of the dams even with zones of tensile stresses in their foundations. These measures include: rational location of the impervious and drainage curtains, in particular, if possible, by transferring the impervious curtains to the upstream side; compression of the rock foundation by means of anchors; second-stage grouting after filling of the reservoirs, etc.
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4.
The presence of tensile stresses in the foundations of almost all concrete dams indicates that there is no need for introducing design limitations prohibiting the formation of tensile stresses in the concrete-rock interface, which in many cases determine the overall dimensions of the dams. In this lies the possibility of substantial lightening of dams and design of economical sections. By applying special constructional measures which recognize the presence of tensile stresses, the reliability of such dams could be made even higher than that of dams of the conventional design, the stress conditions in whose foundations have not been studied.
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Discover the latest articles, news and stories from top researchers in related subjects.Literature Cited
Norms and Technical Conditions. Design of Concrete Gravity Dams on Rock Foundations (SN 123–60) [in Russian] (1961).
P. D. Evdokimov and R. A. Shiryaev, “Laws governing the resistance to sliding of concrete retaining structures on soft foundations”. [in Russian], Proceedings of the First International Congress on Rock Mechanics, NIIOSP, Moscow (1967).
H. Link, “The sliding stability of dams,” Water Power,21 Nos. 3, 4 and 5 (1969).
Yu. A. Fishman, “Development of rock mechanics and investigations of rock foundations of hydraulic structures in the USSR,” “Transactions of the Gidroproekt Institute,” “Rock Foundations of Hydraulic Structures” [in Russian], Collection No. 33 (1974).
Yu. A. Fishman, “Investigation of the kinematics of failure of a blocky rock foundation during the process of sliding of concrete structures,” Proceedings of the All-Union Conference on “Methods of Determining the Stress Conditions and Stability of High-Head Hydraulic Structures” [in Russian], MISI (1972).
Yu. A. Fishman and E. G. Gaziev, “In situ and model studies of rock foundation failure in concrete block shear tests,” Third International Congress on Rock Mechanics, Denver (1974).
P. D. Evdokimov and D. D. Sapegin, Strength, Sliding Resistance, and Deformability of Foundations and Structures on Rock [in Russian], Énergiya, Moscow (1964).
Yu. A. Fishman, V. S. Panfilov, and V. M. Alekseev, “Stress distribution in foundations of sliding blocks,” Transactions of the Gidroproekt Institute, “Rock Foundations of Hydraulic Structures” [in Russian], Collection No. 33 (1974).
Design and Construction of Large Dams, Vol. 4: Ways of Ensuring Strength of Foundations and Stability of Dams and Reservoir Banks [in Russian], (from the Proceedings of the Ninth International Congress on Large Dams). prepared by M. M. Grishin and P. G. Evdokimov under the general editorship of A. A. Borovoi.
I. Bellier, “Le barrage de Malpasset,” Travaux,50, No. 389 (July, 1967).
R. R. Tizdel', “Deformations of rock foundations of high dams after filling the reservoir,” Gidrotekh. Stroitel'., No. 6 (1970).
S. Ya. Eidel'man, “Opening of contact joints and decompression of rock foundations under the first pillars of the river-channel dam at the Bratsk hydroelectric plant,” Izvestiya VNIIG,94 (1970).
K. A. Knyazev and S. Ya. Eidel'man, “Experience with operation of hydraulic structures at the 50th Anniversary of the Great October Bratsk hydroelectric plant,” Gidrotekh. Stroitel'., No. 12 (1973).
F. P. Lacy and G. L. Van Schoick, “TVA concrete gravity dams, uplift observations and remedial measures,” Proceedings of the Ninth International Congress on Large Dams, Istanbul (1967).
F. Sabarly, “Les injections el les drainages de barrages en roches pui permeables,” Geotechnique, Nos. 2 and 8 (1968).
G. Laa, F. Anton, and J. Hernandez, “Auscultacion hidraulica de presas,” Proceedings of the 11th International Congress on Large Dams, Madrid (1973).
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Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 3, pp. 20–25, March, 1975.
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Fishman, Y.A. Stress conditions in rock foundations of concrete gravity dams. Hydrotechnical Construction 9, 235–243 (1975). https://doi.org/10.1007/BF02380720
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DOI: https://doi.org/10.1007/BF02380720