Selection of the revetment on the upstream slope of the upper reservoir at the Zagorsk pumped-storage station and its condition after seven years' service

Abstract

1. The use of wood boards in expansion and working joints of the concrete slopes of PSS reservoirs in the variable level zone is impermissible. In the winter the board works as a wedge, destroying the concrete. 2. Selection of the concrete composition and the technology of its placement should be done at a separate test area under conditions of the construction site, i.e., before placing the concrete in the design structure. 3. In the case of dispensing with vertical concrete retaining walls for the upstream slope of PSS reservoirs and sufficient supplies of sand-gravel mixture in the construction zone, it is necessary to specify more gentle slopes with a steepness of not more than 1\3n8 and with a revetment of a sand-gravel mix with an increase of cobble. The process of placing such a revetment during construction is practically all-weather, which shortens the construction time as a whole. When the PSS reservoirs during 24 hr have a complete cycle of emptying to the dead storage level (DSL) and filling to the normal pool level (NPL), slope revetments with a sand-gravel mixture of the design thickness are more maintainable than concrete filterless revetments. 4. In the case of a filterless revetment with stiff fine-grained concrete of the slopes of PSS reservoirs with a steepness of 1\3n3.5 and steeper, it is necessary to use the already tested special concrete-placing complexes and to provide pressure-relief drains in the revetment slabs themselves.