Results of field observations on ice passage through the structures of the Krasnoyarsk hydroelectric plant

Abstract

One particularity of hydraulic construction on most rivers of the U S~ is the necessity of passing ice through the structures. The requirements of safe passages of ice through the structure~ on rivers with significant spring ice runs predetermine to a large extent the type of basic structures of thehydraulic complexes, the stages and planning of their construction, and the required dimensions of the spillways, and this is reflected also in the economics of the constructions.Several ice passage systems were tested while constructing the Krasnoyarsk hydroelectric plant, some of which could be used again at other hydraulic complexes. During the springs of the 1960-1962 period the ice passage was obtained through a right-bank contraction, during the 1963 spring through an overflow weir having its crest at the level of the river bottom, during the 1964 spring through the spans of an overflow weir with its crest above the bottom and partially through the bottom outlets of Stage I with the invert at the level of the river bottom, during the springs of the 1065-1066 period through the bottom outlets of Stage I, during the 1963 spring through the bottom outlets of Stage II, and starting with the 1968 spring all the ice was retained upstream of the structures.The conditions and characteristics of ice passage through the structure of the Krasnoyarsk hydroelectric plant were described in a series of papers [i-I0]. Thispaper gives the basic results of the generalization of the experience with the retention and passage of ice during the construction of the Krasnoyarsk hydroelectric plant on the basis of the investigations carried out at the S. Ya. Zhuk Gidroproekt and the Siberian Branch of the B, E, Vedeneev