Tunneling method for increasing blasting footage rate and reducing blasting vibration

Abstract

The invention provides a tunneling method for improving explosion driving rate and lowering explosion vibration. The tunneling method comprises the following steps: firstly, arranging an empty slot in a tunnel face; then, respectively arranging peripheral blast holes, slot expansion blast holes, auxiliary blast holes and bottom plate blast holes in the outline periphery of the section of a tunnel to be excavated, between the outline periphery and the empty slot, and in the bottom edge of the section of the tunnel, wherein the slot expansion blast holes and the auxiliary blast holes are arranged in a turn-by-turn way; carrying out time delay detonation in the turn-by-turn way from an inner turn to an outer turn from the slot expansion blast holes in the inner turn to the periphery blast holes in the outmost turn, and finally detonating the bottom plate blast holes; setting the slot expansion blast holes and auxiliary blast holes in the same turn to carry out hole-by-hole time delay detonation. Since the empty slot is arranged in the tunnel face in advance, the defect of big vibration strength caused by a traditional explosion method is overcome; in addition, a good free face for all blast hole explosion is realized, so that deeper blast holes can be drilled in one time to realize one-time deeper explosion drilling footage and smaller explosion vibration, big-drilling-footage explosion excavation under a complex environment can be favorably realized, and excavation efficiency is improved.

Description

Technical field [0001] The invention relates to a tunnel blasting method, in particular to a tunnel boring method capable of reducing blasting vibration on the basis of increasing the blasting footage. Background technique [0002] When tunnel excavation encounters a complex environment section, the first consideration is the impact of blasting vibration on the environment. In order to limit the peak of blasting vibration, the conventional methods are mainly to shorten the blasting footage and reduce the amount of blasting chemicals. As a result, the cost of blasting and excavation is greatly increased, and the driving speed is significantly reduced. [0003] Studies have proved that the main factors that affect the maximum vibration peak of tunnel blasting are: excessive use of clamps for cutting blasting; limited by the delay accuracy of the detonator and the limitation of the section, the number of blasting holes in the same section is too large. The current blasting countermea...

AI Technical Summary

Problems solved by technology

But usually the detonator detonator can only be purchased in 15 sections, up to 20 sections, and the first 8 sections need to be skipped for use, and 4 sections have been reduced, resulting in some tunnel blasting. Concentrated number of blastholes per section, excessive single blasting charge

In addition, wedge-shaped cutting holes can only be arranged with detonators of the same section, which cannot fundamentally change the vibration intensity of cutting blasting

[0006] Although the increase in the number of nonel detonator segments can reduce the amount of blasting charge in a single segment and properly limit the peak value of blasting vibration, the time difference between the blasting intervals of wedge-shaped notch holes cannot be adjusted. no improvement

In the actual blasting cycle, due to the limitation of different detonator sections, blastholes in the same circle position need to be blasted in the same section, and the explosive charge in a single section of the blasthole in the outer circle is still very large, so it is difficult to control the blasting vibration within the ideal range

Therefore, even if more sections of nonel detonators are purchased to reduce the amount of blasting charge in a single section, it is difficult to achieve the ideal effect of controlling the blasting vibration amplitude

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