Blasting method of IV-level massive kata-rocks with mussily-developing wide fracture faces

Abstract

The invention provides a blasting method of IV-level massive kata-rocks with mussily-developing wide fracture faces, and relates to the technical field of tunnel blasting. The blasting method comprises the following steps that drilling is conducted within the 120-degree radiation range of an arch part, an advanced small pipe filled with concrete in advance is installed, and concrete is sprayed forsealing, so that a cantilever ring beam is formed at the position after the next-loop blasting; the arch part and a tunnel face are observed and analyzed on site, the strength of surrounding rock andthe overbreak-underbreak conditions are zoned in the combination of the last loop, a charging structure and a blasting method are adjusted, after the adjustment, the next-loop blasting is started, and the method for adjusting the parameters, such as the setting position of a blasthole and the charging amount, is optimized. The blasting method has the characteristics of having a good blasting effect, improving the safety, improving the working efficiency and reducing the enterprise cost.

Description

technical field [0001] The invention relates to the technical field of tunnel blasting, in particular to a blasting method for level IV massive broken rock with chaotic wide cracks. Background technique [0002] High-speed railways have different regulations in different countries and at different times. The China National Railway Administration defines it as: newly-built passenger-dedicated railways designed to run 250 km / h (including reserved) and above EMU trains, and the initial operating speed is not less than 200 km / h. Features: Newly built, the speed is not lower than 250 and passenger-specific. Difference: In 1962, the early European organization, the International Union of Railways, designated high-speed railways with a speed of 200 kilometers per hour for old lines and 250-300 kilometers per hour for new lines; the Geneva Agreement in 1985 made new regulations: the speed of new passenger-cargo co-linear high-speed railways is More than 250 kilometers, and the spe...

AI Technical Summary

Problems solved by technology

[0004]In the construction of high-speed railways, the tunnel must first be opened up through the mountain. The way to open up is generally to excavate the tunnel after blasting. The tunnel includes the entrance and the horizontal tunnel. , exit, and each mountain itself has different geological conditions, especially when the tunnel mountain is grade IV surrounding rock, joints and fissures are developed, the rock mass is broken, the fissure surface is filled with calcite veins, and the self-stabilization ability of the surrounding rock is poor. The blasting methods for this type of geological rock mass in the prior art have the following deficiencies: the peripheral eye is uniformly charged, and the local broken rock position is severely over-excavated; local over-excavation and local under-excavation phenomena appear on the tunnel vault; secondary blasting or Grouting filling will increase the disturbance of the surrounding rock and increase the risk of collapse, and it is time-consuming and laborious, the progress is slow, and the construction period is difficult to guarantee; in order to reduce the disturbance of the surrounding rock, the excavation footage is small, the cost is high, and the economic benefit is poor

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