Construction method for damped blasting of tunnels

Abstract

The invention relates to a construction method for damped blasting of tunnels. The construction method is characterized in that a working face comprises cutting eyes, auxiliary eyes and peripheral eyes; an air drill is adopted for forming holes in sequence; the working face is divided into a left half-range face and a right half-range face for respectively distributing the segment positions of detonators, wherein the left half-range face adopts even segment positions, the right half-range face adopts odd segment positions; the auxiliary eyes and the peripheral eyes are respectively connected into a group according to 3-5 blastholes in one row; and detonators with same segment positions in different groups can be used repeatedly, and then all the groups are connected in sequence and in series by adopting two segments of detonators, so that the fine differences inside and outside the holes of the detonating tubes are combined together. According to the construction method, the damped blasting measure for combining the fine differences inside and outside the holes are adopted, the detonating tubes with fine differences are connected in parallel and in series for combined use, the detonators with same segment positions in different groups are allowed to be used repeatedly, and the blasting time of the detonators with same segment positions in different groups is staggered through serial two segments of detonators, so that the explosive amount for simultaneous blasting is reduced and the blasting vibration speed is effectively reduced.

Description

technical field [0001] The invention relates to a shock-absorbing blasting construction method for a tunnel, and is especially suitable for subway underground excavation projects in bustling urban areas, and constructions where tunnels pass through large buildings and pile foundations at a short distance. Background technique [0002] In the construction of subway projects in prosperous urban areas, there are often situations where tunnels pass through large structures or bridge pile foundations at close range. When blasting is used for excavation, the blasting vibration may cause destructive effects on buildings or pile foundations; if shield machines are used for construction, the project cost will increase significantly. According to the current national conditions in China, it is difficult to fully promote it. [0003] At present, the tunnel blasting construction mainly adopts non-electric millisecond differential nonel detonators, with a total of 20 sections, and there ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the bottleneck problem of the maximum charge amount of a single-stage detonator on the basis of the existing specifications of pyrotechnic products, provide a construction method for tunnel shock-absorbing blasting, and solve the problem of insufficient detonator sections and the maximum allowable charge amount of a single stage If the contradiction is too small, the blasting vibration velocity can be effectively reduced

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