Explosive column for smooth blasting excavation of foundation surface and excavation technology

Abstract

The invention discloses an explosive column for smooth blasting excavation of a foundation surface and an excavation technology. The explosive column is characterized by comprising blast holes, a buffering layer, a rigid cushion layer, an explosive and a plugging segment, wherein the buffering layer, the rigid cushion layer, the explosive and the plugging segment are arranged at the bottoms of the blast holes; and the buffering layer, the rigid cushion layer, the explosive and the plugging segment are sequentially stacked from bottom to top. The buffering layer is a cylinder; the diameter of the buffering layer is smaller than the diameter of each blasting hole by 0.5 cm-1 cm, and the upper surface and the lower surface of the rigid cushion layer are both conical; and the upper surface and the lower surface of the rigid cushion layer are parallel to each other, and therefore the two-way energy gathering effect can improved. When the explosive column is used, the vertical blast holes, with the circle centers collinear, in rows are drilled in a rock body, and the buffering layer, the rigid cushion layer, the explosive and the plugging segment are sequentially stacked from bottom to top. The technology is simple and convenient, cost is low, operation is easy, adverse effects are reduced because of the two-way energy gathering effect of the rigid cushion layer, the excavation effect is reliable, it can be guaranteed that the dam foundation surface and a slope packway protective layer are formed at a time through excavation, and the explosive column is widely used for excavation engineering of foundation surfaces and slope protective layers of the industries of water conservancy and hydropower engineering, transportation and mines.

Description

technical field [0001] The invention belongs to the technical field of engineering blasting, in particular to a rigid-flexible composite cushion used for blasting and excavating a foundation surface. Background technique [0002] The forming control of the contour surface is an important indicator of the blasting effect. The excavation quality of the foundation surface of the hydropower project and the protective layer of the slope horse road has always been a difficult point in the construction of the hydropower project. In the prior art, the traditional deep hole bench blasting often has low construction efficiency and relatively large damage to the rock mass retained at the bottom of the hole; horizontal pre-splitting or horizontal smooth blasting, the excavation effect is still good, but the construction efficiency is still insufficient. Satisfactory. In recent years, the sequential detonation method of small ladder sections with flexible cushion at the bottom of the h...

AI Technical Summary

Problems solved by technology

In the prior art, the construction efficiency of the traditional deep hole step blasting is often very low, and the damage to the rock mass retained at the bottom of the hole is relatively large; the horizontal pre-splitting or horizontal smooth surface blasting has good excavation effect, but the construction efficiency is still not enough. satisfactory

In recent years, the sequential detonation method between holes in small steps with a flexible cushion at the bottom of the hole, due to the limited cushioning effect of the flexible cushion material on the blasting shock wave, the damage to the bottom of the hole is still relatively large, and the excavated foundation surface has a large fluctuation difference , resulting in a large amount of manual prying and excavation; at the same time, the ordinary energy-concentrating blasting using a wedge-shaped charge tank cannot achieve ideal results due to the limited energy-concentrating effect of the device.

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