Excavation method of barrier lake aerial drainage tunnel

Abstract

The invention provides an excavation method of a barrier lake aerial drainage tunnel. The excavation method of the barrier lake aerial drainage tunnel is characterized in that small space excavation is sectionally adopted, a large tunnel is formed by a manner of successive jacking in sections, at the same time, the top end and the two side ends of each section of the tunnel are continuously strengthened and supported according to successive jacking, and a steel body of each section of the tunnel is formed after strengthening and supporting; during aerial drainage, water constantly scours the bottom surface of soil mass, the bottom surface of the tunnel is hollowed out, the steel body of each section of the tunnel decreases continuously with the bottom surface of the soil mass, and the barrier lake aerial drainage height is further decreased; and the starting position of small space excavation is set in the unilateral direction or bilateral direction of a barrier lake or in a middle open caisson, construction of the open caisson is carried out in one-direction or two-direction manner, and a flow control device is arranged in the steel body of the aerial drainage tunnel or the open caisson. According to the excavation method of the barrier lake aerial drainage tunnel, the earth excavated volume is greatly decreased, the working face is increased by setting the open caisson on anexcavation line, the excavation length of each working face is greatly shortened, and it is conducive to start the aerial drainage and remove danger work in a very short time.

Description

technical field [0001] The invention relates to disaster reduction technology, in particular to a method for excavating a dammed lake discharge tunnel. Background technique [0002] A barrier lake is a kind of barrier body formed mainly by geological disasters such as large-scale landslides and collapses in the river channel. The barrier body blocks the channel and stores water to form a lake. For large barrier lakes, the barrier body is tens of meters above the river bed , the water level of the reservoir has risen sharply, not only will it submerge the upstream, but the dam body with loose structure and poor stability is likely to break the dam, causing floods to the downstream. The higher the water level, the larger the reservoir capacity, and the more serious the disaster. In the shortest possible time, drain the lake water, lower the water level, and eliminate the risk of dam failure. [0003] The main disposal method is to excavate drainage channels, and the available...

AI Technical Summary

Problems solved by technology

This excavation method has many shortcomings: first, the excavation volume is large, the earthwork transfer volume is large, and the slotting speed is slow; Threatened by the second landslide on the mountain; Fourth, during the discharge process, the discharge flow cannot be controlled, resulting in a huge discharge peak and causing floods

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