Double-side wedge-shaped cutting, tunneling and detonating method of especially-big fracture surface tunnel

Abstract

The invention discloses a double-side wedge-shaped cutting, tunneling and detonating method of an especially-big fracture surface tunnel. The to-be-excavated especially-big fracture surface tunnel is divided into an upper step and a lower step to be constructed; as for a to-be-excavated rock mass of the upper step of the tunnel, the double-side wedge-shaped cutting and subsection millisecond delay detonating method is used for excavation; according to double-side wedge-shaped cutting, double-side cutting zones are symmetrically distributed at the lower middle portions of the two sides of a face center line of the upper step, the cutting zones are vertical columnar zones with the plane shapes being wedge shapes, and groove cavities formed by cutting and detonating can provide sufficient smashing expansion space for detonating of various types of shot holes; and according to subsection millisecond delay, millisecond delay detonating is carried out at the positions between rows, detonating of various types of shot holes is carried out, the using rate of various types of shot holes is effectively improved, and the design footage is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of tunnel rock excavation and blasting engineering, and in particular relates to the blasting and excavation construction for super-large cross-section mountain tunnels. Background technique [0002] Due to the constraints of the terrain and the direction of the line, in order to meet the traffic requirements when the wide road crosses the mountains, the cross-sectional area of ​​the tunnel often needs to reach 100m 2 The above is a super-large section tunnel; the drill-and-blast method, as the most economical and efficient rock tunnel excavation method, is currently being widely used in the excavation of various rock-soil tunnels; It is the way of center cutting for blasting excavation. [0003] In view of the fact that there is generally only one free surface during tunnel excavation and blasting, which is not conducive to the crushing and excavation of the rock mass in the tunnel, therefore, it is necess...

AI Technical Summary

Problems solved by technology

The current method of center cutting is to arrange a cut area near the center of the section, but when the excavation section of the tunnel is too large, only arranging a center cut area cannot provide enough space for the rock mass to break and bulge, resulting in bouncing When blasting the hole and surrounding holes, the rock mass clamping effect increases, the utilization rate of the blast hole decreases, and it is difficult to achieve the design cycle footage, which will easily lead to a lag in the tunnel construction period, and the tunnel construction cost will increase significantly

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