Diversion channel closure method

Abstract

The invention discloses a diversion channel closure method. During excavation of a diversion channel, a rock step is reserved to serve as a closure step, a rock step is reserved at the position of an outlet of the diversion channel to serve as a river diversion and slope protection step, and a 30-60-degree angle is formed between the river diversion and slope protection step and the water flow direction. During closure, a berm is built, and the reserved closure step is made to be located at the position of a slope toe on the lower portion of the closure gap section of the berm. When two berms are used for closure, closure gaps are arranged in a stagger mode, reverse occupation is achieved, and the river diversion and slope protection step is lengthened to be a construction trestle. By means of the reserved closure step, the hydraulic index of closure gaps is reduced, riprap stability is improved, the split ratio of a drainage gallery is increased, and closure difficulty is reduced; the flow state at the outlet is changed by means of the river diversion and slope protection step, and bank slope scouring is prevented or reduced; meanwhile, the river diversion and slope protection step is part of a closure trestle, and the length of the trestle is reduced.

Description

technical field [0001] The invention relates to a method for intercepting a diversion open channel, which belongs to the field of water conservancy and hydropower engineering. Background technique [0002] Open channel diversion is relatively common in the construction of large river hydropower projects, and open channel closure is an important part of project construction. Diversion open channel interception generally has large interception flow, poor diversion conditions, and the open channel floor roughness is small, which is not conducive to the stability of throwing and feeding materials, large material consumption, large loss of interception materials, and difficulty in interception. For the difficult diversion open channel interception, most of the previous engineering practices used wide dikes, double dikes or multiple dikes to intercept the flow. However, the simple above-mentioned methods can only reduce the hydraulic index of Longkou to a limited extent, and it is...

AI Technical Summary

Problems solved by technology

The present invention pre-sets the interception sill to reduce the difficulty of diversion open channel interception, and overcomes the high hydraulic index, long duration, large throwing material particle size, large amount of special materials, poor throwing feeding stability, and large throwing feeding loss during the interception process. , and many other issues such as high investment in closure projects

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