Rock roadway deep-hole multi-wedge straight-hole internal subsection micro-difference cutting blasting method

Abstract

The invention discloses a rock roadway deep-hole multi-wedge straight-hole internal subsection micro-difference cutting blasting method. A multi-wedge straight-hole inter-subsection micro-difference blasting technology is adopted to realize progressive enlargement of a cutting cavity and progressive deepening of the cutting cavity, a deep-hole column-shaped charge subsection micro-difference blasting technology is adopted to solve the belly phenomenon at the bottom of the cutting cavity, and the deep-hole cutting blasting method can realize the effects that a large cutting cavity and a cuttingcavity 3.0 m deep can be obtained, the percentage of large gangue dumped by cutting is small and the throwing distance of waste rock is reduced to 25-30 m. Sequential initiating is performed according to a primary oblique hole + a six-direction energy-gathering straight hole I section detonator, a secondary oblique hole first section + a central straight hole hollow hole II section detonator, a secondary oblique hole second section + a central straight hole bottom charging section + a tertiary oblique hole III section detonator to form a final cutting cavity, then auxiliary holes, caving holes and bottom holes are initiated by adopting a IV section detonator, and peripheral holes are initiated by adopting a V section detonator to complete full-section blasting; and the large cutting cavity can be provided, the free surface is enlarged, and the blasting efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of rock roadway blasting, and in particular relates to a method for segmental differential cutting blasting in deep holes with multiple wedges and straight holes in rock roadways. Background technique [0002] In the excavation of various rock roadways (tunnels), the drill and blast method still occupies the main position in the excavation due to its own advantages. In the coal mine rock roadway excavation in my country, according to the depth of the blast hole, it can be divided into: shallow hole blasting (blasting hole depth <1.8m); medium and deep hole blasting (blasting hole depth 1.8m ~ 2.5m); deep hole blasting Light explosion (blasting hole depth 2.5m ~ 5.0m); ultra-deep hole light explosion (blasting hole depth above 5.0m). When drilling and blasting excavation, most of the drilling rigs in domestic coal mines use 2.6-meter drills, and most coal mine rock roadways generally have a footage of abou...

AI Technical Summary

Problems solved by technology

[0003] At present, in all kinds of engineering blasting, although deep hole cutting blasting methods such as oblique eye, straight eye, double wedge shape and multi wedge shape have been explored in the deep hole cutting blasting technology, but for single free vertical deep hole blasting such as cut blasting In terms of blasting, due to the clamping effect of the rock at the bottom of the hole, especially the deeper the blasthole, the stronger the clamping effect, there will often be a large number of residual holes after blasting, resulting in obvious bulging in the middle, resulting in cutting The depth is difficult to exceed 2.6m, which reduces the blasting effect and blasting single-cycle footage, which affects the cutting effect

In addition, when carrying out deep hole blasting, especially when the rock is relatively hard, in order to improve the cutting effect, the holes are usually arranged very densely and the amount of charge is large, resulting in a large amount of charge in one blast and serious damage to the surrounding rock. The blasting shock wave is large, and the gangue throwing distance is long, etc.

Images