Ⅰ、方法总述在河中筑壩的施工断流工程,当流量比较少时,在今日的技术条件下尚不特别困难,但是当流量大、河道深、流速高时,如在苏联及美国境内河流中所遇到的,其条件颇为不利,可能变成为冒险的举动,而造成工程费用巨大及拖延时间的损失。早在1935年,苏联伊士拔施教授已作有施工断流的理论研究[注1],以后法国的勃郎士工程师又作了补充,见“水流中抛石筑壩技术”[注2] Ⅰ. Description of Method It is not particularly difficult under today’s technical conditions when the flow rate is relatively small, but when the flow rate is large, the depth of the riverway is high, and the flow velocity is high, as in the rivers in the USSR and the United States Encountered conditions that were rather unfavorable and could turn out to be adventurous and resulted in huge project costs and delays. As early as 1935, the Soviet Union, Professor Ezbooths has made a theoretical study of construction cut off [Note 1], after the French Bu Langshi engineers also made a supplement, see the “flow of rock and roll dam technology” [Note 2 ]