Requirements for Amendments to Regulatory Documents on Design and Construction of Earth Dams
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Vol. 54, No. 4, November, 2020
REQUIREMENTS FOR AMENDMENTS TO REGULATORY DOCUMENTS ON DESIGN AND CONSTRUCTION OF EARTH DAMS N. F. Aripov1 and S. A. Lyudva2 Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 5, May 2020, pp. 50 – 53.
The article provides reasonable proposals for amending the current regulatory documents of the Russian Federation, regulating the quality control of dumping coarse grained soil into the dam body. In addition, the standards of Russia and the USA are also compared. Keywords: earth-and-rockfill dams; coarse-grained soils; quality control; soil density; representative sample; grain size distribution; soil structure; fine grained soil; rigid frame; filler; matrix.
be 0.8 – 1.0 m3, and those with fragments up to 450 mm should be at least 8.0 m3. In the contemporary practice of designing and constructing rockfill and earth and rockfill dams, coarse-grained soils with considerable coarseness are used very often (Fig. 1). Russian standards [6] suggest the drilling of pits with volumes up to 40 – 50 m3 to investigating the quality of coarse-grained soils placement in the dam body with the content of coarse fractions of up to 700 – 800 mm. The American standard [5] presented in the notes of the Table A1.2 recommends determining the density of such soils in exceptional cases. Such a difference in the requirements of these standards does not enable to assess objectively the quality of the work performed. The American standard require to check the quality of soil placement over large areas by taking a large number of samples in small-volume pits and statistical data are gathered based on that. However, all small-volume samples are unrepresentative and cannot characterize objectively either the placement density or the true granulometric composition of coarse-grained soil. It is a known fact that the size of the pits for taking representative samples should exceed at least 5 times the maximum size of fragments of coarsegrained soil. If Russian standards are applied for taking representative samples, as illustrated above, it is necessary to drill pits with very large volume. For example, the pits of 180 – 200 m3 were drilled to control the quality of stone filling in its slopes and crest, and the weight of the samples taken exceeded 350 – 400 tons during the construction of the high-level Nurek dam (300 m). Samples were taken at the rate of one sample per 50,000 m3 to determine the density of the stone placement and one sample per 10,000 m3 to investigate the actual granulometric composition. Such volumes of
The article Method of quality control of placement of coarse-grained soils in pits of reduced size during the construction of dams [1], published in the journal Gidrotekhnicheskoe stroitel’stvo, aroused wide interest among foreign experts. The article was also published in the London Journal of Engineering Research [2], in the International Academic Journal of England [3]; it was also recommended for the competition of the best works for 2019 [4]; in 2020, the authors were invited to interna
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