Jet flow and drop flow energy dissipation structure for overflowing of shore-side flood protection gap of gravity dam

Abstract

The invention discloses a jet flow and drop flow energy dissipation structure for overflowing of a shore-side flood protection gap of a gravity dam. A shore-side gap is arranged in a dam section close to a river bank at one side; a plunge pool is arranged downstream the shore-side gap; one side of the plunge pool is a bank slope; a shore-side platform is arranged at the top of the bank slope; a shore-side guide wall is arranged on the shore-side platform and is connected with the tail end of the shore-side gap; the shore-side platform is connected with the plunge pool via the bank slope; separating piers are arranged at the other side of the shore-side gap opposite to the shore-side guide wall and are used for preventing water flow in the gap from being turned over outwards. The radius of the shore-side guide wall is 4H to 6H; the length of the shore-side guide wall is 2H to 4H; the height of the shore-side guide wall is larger than 0.4H; the included angle of the tail end of the guide wall and the bank slope is 5 to 15 degrees; the gradient of the bank slope is larger than 1:0.3; the water depth of the plunge pool is larger than 0.2 Delta Z; H represents the difference of the highest flood protection water level and the bottom elevation of the gap; Delta Z represents a designed difference of the upstream water level and the downstream water level. The bank slope is provided with no packway. The jet flow and drop flow energy dissipation structure is good in energy dissipation effect, good in water flow condition, free of phenomenon of deflected water flow, and free of phenomenon of concentrated impact. The main flow does not wash against the bank slope, and the shore-side flow speed is small. The jet flow and drop flow energy dissipation structure is manufactured from conventional concrete, so the manufacturing cost is low.

Description

technical field [0001] The invention belongs to energy dissipating equipment used in water conservancy and hydropower projects, in particular to an energy dissipating structure used for overflowing gaps on banks of gravity dams. Background technique [0002] During the construction period of the gravity dam, it is often necessary to reserve a flood relief gap in the dam body, so that the flood can flow through the gap during the flood season, so as to reduce the water level of the reservoir and ensure the safety of the poured dam section. The reserved gaps in the dam body can be arranged in the non-overflow dam section on both sides of the dam. The advantages of this arrangement are: the structure of the non-overflow dam section is simple, and the construction can be resumed quickly after the flood; during the flood season, the overflow dam The metal structure installation and concrete pouring of the section can be carried out continuously; the construction period of the dam...

AI Technical Summary

Problems solved by technology

The disadvantage is that the flow gap is close to the shore, the water flow is complex, the energy dissipation is insufficient, and the water flow is easy to cause erosion to the bank slope.

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