A method and device for repairing underwater hollowing defect of ship lock navigation wall pile foundation on gravel layer foundation

Abstract

The invention provides a method and structure for repairing the underwater hollowing defects of the ship lock navigation wall pile foundation on the gravel layer foundation, including anti-seepage concrete pouring piles, plain concrete piles, concrete connecting beams, planting bars and non-dispersed concrete fillers, anti-seepage Concrete cast-in-place piles are arranged in a row at the water-facing surface 2m outside the underwater hollowing defect of the pile foundation of the navigation wall. The wall is continuously poured, and the piles are 2-4m deep into the bedrock. Go deep into the bedrock 1-2m, set the concrete connecting beam on the top of the anti-seepage concrete pouring pile, the concrete connecting beam and the pile foundation of the navigation wall are connected by planting bars; the underwater hollowing defects of the pile foundation of the navigation wall are made of non-dispersible concrete with unclear foundation Fill pouring backfill. The invention has the advantages of good anti-washing effect, which is beneficial to popularization and application of anti-scouring protection such as tailwater guide walls of powerhouses of hydropower stations and navigation walls of ship locks, and has huge safety and economic benefits.

Description

technical field [0001] The invention relates to the technical field of water conservancy and hydropower engineering, in particular to a method and a device for repairing underwater hollowing defect of a ship lock navigation wall pile foundation on a gravel layer foundation. Background technique [0002] After the dam is built, it is a common phenomenon that the sand and gravel river bed under the dam is scoured and cut down. The scour forms a deep river channel, and the discharged water will rush to the navigation wall of the approach channel. After the gravel around the pile foundation at the lower part of the navigation wall is washed away, causing A section of the pile foundation is exposed above the river bed. Under the impact of perennial water flow, sand and gravel at the exposed section of the pile foundation, the concrete protective layer was partially peeled off, resulting in exposed steel bars. After the original closed sand and gravel layer was washed away, the l...

AI Technical Summary

Problems solved by technology

[0005] (1) The dry land construction plan adopts conventional earth-rock cofferdams, closes the downstream navigation wall, cleans the sand and gravel to the strong weathered rock surface in dry land, and then pours concrete to form a new wall according to the designed section, so as to strengthen the navigation of this section The purpose of the wall foundation, but this traditional method has a huge investment, and the investment in temporary measures (earth-rock cofferdam engineering volume) exceeds the main project, which is uneconomical and unrealistic

[0006] (2) The underwater direct repair construction plan requires underwater sand and gravel to clear the foundation to the bedrock, so as to have the energy efficiency of pouring underwater concrete walls. At present, it is impossible to use construction machinery to clean the underwater sand and gravel layer, and the cost of underwater artificial foundation clearing is huge , not feasible

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