Construction Of Earth Dams Research Articles

Drilling and blasting operations in the cyclic-flow technology of earth-dam construction

Drilling and blasting operations in the cyclic-flow technology of earth-dam construction

Conference on the Theme “Methods of Construction of Earth Dams with Integrated Mechanization of Protective Material Placement”

Conference on the Theme “Methods of Construction of Earth Dams with Integrated Mechanization of Protective Material Placement”

Quality control during construction of earth dams

Quality control during construction of earth dams

Damming without embankments of the Dnepr River at the site of the Kanevsk hydroelectric plant

1. The experience here described confirmed the possibility of damming large rivers, without constructing embankments, at hydraulic developments, by placing fine-grained sands by hydraulic dredges. This method of damming river channels is especially convenient if in the project region the rock and rubble material are obtained from quarries located at great distances. 2. The method of damming river channels without using embankments permits closing off a narrow passage, within a short period, by constructing a hydraulic-fill dam by means of suction dredges, without employing floating cranes, pontoon bridges, or other auxiliary equipment. 3. When damming a river channel without constructing embankments, a discharge channel with a small drop should be constructed and a sufficient volume of sand capable of being adequately handled by suction dredges should be supplied. 4. For the construction of river-channel earth dams with very wide bases (and gentle slopes on the downstream side), the method of damming the channel without constructing embankments by placing local soils can save large volumes of rock and rubble. 5. The damming of the Dnepr River at the site of the Kanevsk hydroelectric plant permitted saving 54,000 m3 of rock and 17,000 m3 of rubble; the total economy resulting from the damming of this river without constructing an embankment was 750,000 rubles.

Quick splicing of polyethylene membranes by means of nichrome bands

1. The installation for contact splicing of polyethylene membranes by means of nichrome bands is of simple construction, can be easily operated, is more efficient, and permits obtaining high-quality splices. 2. The method here described may be used for preliminary preparation of the blankets in the shop or the field, as well as for splicing the blankets at the construction site. 3. Contact splicing with nichrome bands may be advantageously used when the volume of work is large, for example, in the construction of long headrace or irrigation canals, or in the construction of large earth or rockfill dams with screens consisting of polyethylene membranes.

Design and construction of earth and rockfill dams

Design and construction of earth and rockfill dams

Shear strength of coarse fragmental soils

1. The construction of high earth and rock dams requires that investigators obtain exact data on the shear resistance and deformative properties of coarse-fragmental soils. 2. Investigations carried out in recent years here and abroad have made it possible to establish the following: a) The angle of internal friction of coarse-fragmental soils largely depends on the density of packing, soil stresses, and size of the particles composing the soil; b) The angle of internal friction of coarse-fragmental soil can exceed numerically its angle of repose and is within limits up to 54° and sometimes higher; c) Investigations of shear strength can be conducted both by shear instruments and by consolidometers, provided Dinst/dfrac≥5; d) One should try to investigate coarse-fragmental soils of natural granular composition using field instruments. 3. The angle of internal friction of coarse-fragmental materials decreases with an increase of normal stresses and to a greater degree for rock than for gravel in the same range of stresses. 4. Further investigations of the shear strength of coarse-fragmental soils should be aimed at perfecting large devices (preference should be given to consolidometers) and methods of investigation.

Discussion of “Problems in Design and Construction of Earth and Rockfill Dams”

Discussion of “Problems in Design and Construction of Earth and Rockfill Dams”

Construction of earth dams and high-grade embankments at the Kuban’ hydroelectric development

Construction of earth dams and high-grade embankments at the Kuban’ hydroelectric development

Construction of high earth coffer dams in two stages on mountain rivers with flood overflow at an intermediate elevation

1. The erection of coffer dams in two stages with overtopping at an intermediate elevation removes the existing limitations in the time of erection and permits increasing the total height of the coffer dams, thus decreasing the sizes of diversion structures, and often shortening the construction time of hydrocenters. 2. In the case of the Toktogul’sk HES the decision to pass the flood through the tunnel and over the crest of a partially erected earth coffer dam made it possible to dam up the Naryn River at the beginning of 1966, and thereby to begin preparatory work in the pit of the dam one year ahead of time. 3. The earthen 30-m high Stage I coffer dam, through which a discharge (600 m3/sec) exceeding the design value by 30% was passed, withstood the flood without any damage. This shows the dependability of the adopted design of the spillway coffer dam and the good quality of the work. 4. The successful passage of the flood at the Toktogul’sk through the partially erected earth coffer dam makes it possible to recommend this method for other projects. The maximum effect can be expected in the construction of earth or rock-filled dams, where the coffer dam, as a rule, becomes part of the dam. 5. The 1966 flood at the Toktogul’sk HES passed with discharges exceeding those of the design and with heads lower than the design; this requires a special analysis of the discharge capacity of tunnels and pipes of large cross sections.

Discussion of “Problems in Design and Construction of Earth and Rockfill Dams”

Discussion of “Problems in Design and Construction of Earth and Rockfill Dams”

Problems in Design and Construction of Earth and Rockfill Dams

In the design and construction of earth and rockfill dams many problems exist for which satisfactory solutions are not presently available. The ten most urgent problems concerning embankment design and construction are listed. For each problem, methods of attack are appraised under the following headings: (a) by collection of existing data; (b) by theoretical analysis or laboratory research; (c) by full scale field observations; and (d) by defensive design measures. The problems are grouped in three priority categories. All of the data accumulated in response to a questionnaire circulated both within and outside the United States are given for each of the problems.

Tuttle Creek Dam of Rolled Shale and Dredged Sand

To fit available materials, the design of Tuttle Creek Dam central Kansas includes major volumes of shale-limestone constructed as a rolled fill, and of sand deposited by dredging directly into place two types of fill not commonly employed present-day earth dam construction. The reasons for choosing this design are explained, together with experiences learned during construction. The paper covers primarily the earthwork and foundation aspects of the project, of which the other more unusual features are closure in the wet and handling an area of weak clay foundation partly by excavation and partly by exceptionally wide berms.

Tuttle Creek Dam of Rolled Shale and Dredged Sand

To fit available materials, the design of Tuttle Creek Dam central Kansas includes major volumes of shale-limestone constructed as a rolled fill, and of sand deposited by dredging directly into place two types of fill not commonly employed present-day earth dam construction. The reasons for choosing this design are explained, together with experiences learned during construction. The paper covers primarily the earthwork and foundation aspects of the project, of which the other more unusual features are closure in the wet and handling an area of weak clay foundation partly by excavation and partly by exceptionally wide berms.

The Influence of the “Hydraton” Method on the Stability of the UPstream Fill in Earth Dam Construction

The Influence of the “Hydraton” Method on the Stability of the UPstream Fill in Earth Dam Construction

Compaction on cultivated soils

Many soils which, in their native state were mellow, of low apparent density, and highly permeable to water, have become compact and highly impermeable under cultivation. Other soils, although cultivated as often, still remain fairly permeable. Soils men have long advocated the necessity of reducing the amount of cultivation, and the desirability of selecting a time for field‐operations when the moisture‐content of the soil is such that the bearing power of the soil is adequate to safely carry the equipment. The importance of soil‐particle size in relation to compaction has not been stressed. Observations in citrus orchards in southern California indicated that cultivation produced the highest densities and the greatest reduction in water‐penetration on those soils in which there was a wide range of particle‐sizes, such a s the gravelly loams derived from igneous rocks high in quartz. This idea is in agreement with the FULLER curve concept used in designing concrete mixes, and in the construction of earth fill dams [see 3 of “References” at end of paper].

Quabbin Dike Built by Hydraulic Fill Method

The thorough investigations of materials available for earth dam construction furnish not only the proper information by which to decide the type, dimensions, and cost of the earth dam to be built, but they furnish sufficient data to enable contractors to bid intelligently. Such bidding tends toward more economical and satisfactory construction.

Soil Compaction Control for Rolled Earth Dam Construction

Soil Compaction Control for Rolled Earth Dam Construction