ment works; to obtain a broad zone of simultaneous conduction of works; to improve access to the runner pit; to improve the quality of concreting the runner pit (without toothing); and to faciliate the installation of the linking band and lining between the LRGA and cone of the spiral casing.

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In recent years designers have been using increasingly more often asphaltic concrete core walls (ACWs) as the main watertight element in designs of rockfill dams [1].Thanks to the relative simplicity and accessibility of the technology, the efforts of our specialists were aimed mainly at the search for and development of technologies of constructing poured asphaltic concrete ACWs [2]. Suggestions on the technology of constructing precast asphaltic concrete core walls are also known [3], and the placement of compacted asphaltic concrete in the body of core walls of earth dams is widely practiced abroad.Compacted asphaltic concrete, in comparison with poured, contains a smaller amount of bitumen. As a consequence of this, it is more viscous and cannot self-compact upon placement. Despite the use of this material being limited to positive temperatures, its wide use is promoted by a lower cost and lower lateral pressure coefficient (of the order of 0.15-0.30), which lessens the probability of the bitumen being squeezed out into the soil of the transition zones and reduces the force of the core walls on the shoulders of the dam.The construction of compacted asphaltic concrete diaphragms abroad is carried out with the use of self-propelled or towed asphaltic concrete placers. An asphaltic concrete placer represents a unit consisting of a power plant, receiving and dispensing hoppers for asphaltic concrete and soil with gate feeders, and compacting mechanisms (vibrating rollers or vibrating plates). The asphaltic concrete and soil of the transition zones are delivered in buckets to the unit and reloaded into the hoppers. The machine forms a trench out of the soil with simultaneous placement of the asphaltic concrete in it continuously and layerwise, primarily with a layer not more than 20 cm thick. Compaction of the placed materials is done by the unit itself, and their additional compaction (if necessary) is done by a vibrating roller moving behind the unit.Operation with the asphaltic concrete placer presumes the need for the clear-cut interaction of all links of the chain: asphaltic concrete plant--quarry--transport--construction site.The use of compacted asphaltic concrete in Soviet hydrotechnical practice is being held up mainly by the absence of specialized asphaltic concrete-placing equipment. At the same time, as it seems, the problem of the accelerated introduction of compacted asphaltic concrete can be solved sufficiently effectively not only by means of special equipment but also on the basis of using Soviet quantity-produced equipment. The article will familiarize readers with the developments of the All-Union Scientific-Research Institute of Hydraulic Engineering (VNIIG) in this direction.In the developed technology, unlike the foreign analogues, the body of the core wall is formed by means of climbing-traveling forms. The proposed technology of constructing a compacted asphaltic concrete core wall consists in the following (Fig. 1). Climbing--traveling forms 2 and 3 are installed along the line of the ACW ...

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