Construction of cofferdams at the Dnepr-II hydroelectric station

Conclusions

• 1. Underwater clearing of blocks from the bottom is unproductive, expensive, and inefficient. It is necessary to. investigate the bottom more thoroughly and to use appropriate cutoff measures for each section.

• 2. The assembly of sheet pile cells by a combination consisting of a Kirovets floating crane with four winches, a boat, two barges, two floating templets, and an arched templet for incomplete cells under conditions when driving the sheet piling into the ground is not required can be done at an average rate of one cell a day.

• 3. In cases when a highly productive construction method is used (as, for example, the assembly of sheet pile cells) manual, low-productive operations should not be used (as, for example, the assembly of screens for retaining the graded filter inside the cells). In such a case one should use mechanized filling of ungraded rubble.

• 4. The designs of the floating templet, arched templet, and device for the tremie method of underwater concreting during the construction of the Dnepr-II station should be considered successful and suitable for use under such condition.