A Blasting Construction Method of Equidistant Fan-shaped Holes in Tunnel Excavation and Expansion Area

Abstract

The invention discloses a tunnel mine drawing groove area equidistant sectoral hole arrangement blast construction method. The method comprises the steps of 1, designing a drawing, wherein blast holes are reasonably arranged according to the tunnel lithology grade and the tunnel blast design requirement, and an equidistant sectoral hole arrangement method is utilized to conduct CAD software drawing; 2, erecting an instrument and conducting surveying and lofting, wherein the drawing in the first step is utilized, a vertical line is made in the profile plane of the joint of the blast holes, a lofting rod or a ready-made anchor rod is arranged and fixed on the vertical line, and a nylon rope is hung and serves as a drill lofting line; 3, conducting drilling, wherein the drawing in the first step is utilized, and a drill reference point construction method is adopted to conduct construction; 4, conducting charge blast, wherein powder charging, blocking, blast network connection, alerting and blast initiating are conducted according to the designed detailed requirement for segmentation of the powder charge volume of each blast hole, and the powder charging structure. The tunnel mine drawing groove area equidistant sectoral hole arrangement blast construction method is easy to learn and operate, and hole arrangement and lofting on a palm mine drawing groove area are precisely conducted.

Description

technical field [0001] The invention relates to the technical field of tunnel blasting construction, in particular to a blasting construction method for equidistant fan-shaped holes in a tunnel excavation and expansion area. Background technique [0002] Tunnels and underground projects play an important role in the construction of the national economy. With the rapid development of national construction, the construction of tunnel projects increasingly needs to solve the problem of how much, how fast, and how cheap. In the short term at present and in the future, the drilling and blasting method will still be the main method of tunneling, and the success of the blasting depends on whether the cutting is successful, and the size of the footage depends on the depth of the cutting, so it is necessary to study the cutting method suitable for the surrounding rock conditions. Groove technology maximizes the blasting footage on the premise of ensuring the stability of the surround...

AI Technical Summary

Problems solved by technology

[0003] With the continuous excavation of the tunnel, the height of the upper mountain where the excavation face is located is increasing, and the stress of the rock is increasing. At the same time, the toughness and strength of the surrounding rock are increasing, the integrity of the surrounding rock is improved, the explosiveness is reduced, and the cutting effect is often not good. Ideal, with the same drilling depth, the circular footage after blasting is reduced, and even the clamping force of the surrounding rock is too large, the cutting is squeezed to death by blasting, and half of the hole is not stripped by blasting, requiring re-drilling and supplementary blasting

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