Smooth blasting method for tunneling

Abstract

The invention relates to a smooth blasting method for tunneling, and belongs to the technical field of blasting engineering. According to the method, a peripheral smooth blasting hole charging structure of axial non-coupling water interval shaped charge blasting is adopted, a main blasting area and an edge blasting area of a tunneling tunnel face are determined firstly, a main blasting center hole is formed in the center of the main blasting area, and a plurality of large-diameter empty holes are symmetrically formed with the main blasting center hole as the center; a plurality of layers of main blasting holes are symmetrically formed in the outer side of the large-diameter empty hole with the main blasting center hole as the center, and a plurality of peripheral smooth blasting holes are formed in the edge blasting area; an axial non-coupling main blasting hole charging structure is arranged in a main blasting center hole and a main blasting hole of the main blasting area, and a peripheral smooth blasting hole charging structure for axial non-coupling water interval shaped charge blasting is arranged in a peripheral smooth blasting hole; and the main blasting center hole, the main blasting holes and the peripheral smooth blasting holes are sequentially detonated hole by hole. The jet flow formed by the energy gathering groove and the water bag generate a 'water wedge' effect in the blasting process to promote the initial crack growth of the rock, and water mist is formed to reduce the dust concentration in the blasting process.

Description

technical field [0001] The invention relates to a smooth blasting method for tunnel excavation, which belongs to the technical field of blasting engineering. Background technique [0002] Smooth surface blasting usually refers to controlling the scope and direction of blasting to make the rock surface smooth and flat after blasting, to prevent cracking of the rock surface, to reduce the workload of over-excavation, under-excavation and support, to increase the stability of the rock wall, and to reduce blasting. It is a technology to control the excavation profile of the rock mass. The smooth blasting technology is used as a technical means to protect the reserved rock mass. Hole 2 detonates sequentially from the middle to both sides. As a technical means to protect the reserved rock mass, smooth blasting has been widely used and developed in the construction process of tunnels, slopes, nuclear power plants, etc. [0003] At present, most of the smooth blasting holes are bl...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the smooth blasting holes are blasted at the same time. Simultaneous blasting of the smooth blasting holes will cause greater damage to the reserved rock mass, which is not conducive to the formation of a more stable slope wall, and the blasting vibration is also relatively large. , which is not conducive to the stability of the surrounding rock; secondly, more dust will be generated at the same time, and the longer ventilation time will affect the efficiency of the cycle footage, and it will also have a greater impact on the health of the construction workers on site; moreover, light blasting holes The main reason for detonation at the same time is that it is difficult to set the detonation delay time due to the large number of light blast holes.

Images