Vibration absorbing method for cut presplitting blasting

Abstract

The invention relates to a vibration absorbing method for cut presplitting blasting, which comprises the steps that blasting tunneling is performed on a face of a subway tunnel; a gadder is used to drill blastholes including presplitting blastholes, cutholes, assistance holes, periphery holes and bottom plate holes; the presplitting blastholes are a group of transversely arranged blastholes that are located 500mm-600mm above the cutholes; the presplitting blastholes adopt mixed connected kerf cartridges for explosive loading; the cutholes, the assistance holes, the periphery holes and the bottom plate holes adopt common emulsion explosive loading, and adopt millisecond nonel detonators; and the presplitting blastholes, the cutholes, the assistance holes, the periphery holes and the bottom plate holes are initiated in sequence. The vibration absorbing method has the benefits that as a presplitting surface and a presplitting crushed zone are formed above the cutholes, the vibration is reduced and absorbed in transmission paths, the vibration velocity caused by the cut blasting is reduced obviously, and blasting vibration can be controlled effectively. Compared with the traditional smooth blasting, the maximum blasting vibration velocity can be reduced by 30%, and effects on protected heritages along a line are reduced.

Description

technical field [0001] The invention belongs to the excavation and blasting technology of urban subway tunnels, and in particular relates to a cutting pre-splitting blasting shock absorbing method, which is applicable to the blasting of urban subway tunnels passing through cultural relics areas in a short distance in rock formations. Background technique [0002] At present, with the rapid development of urban rail transit, underground railways in cities and suburbs, elevated railways on the ground and ground rails constitute a transportation network. Subway traffic has become the most important part of urban traffic because of its convenience, speed, environmental protection, and large transportation capacity. [0003] In cities where the geological conditions are dominated by rocks, the drill and blast method is usually used for construction. The drill and blast method has the advantages of low construction cost, high excavation efficiency, and easy operation, and has beco...

AI Technical Summary

Problems solved by technology

However, during the construction process of the drilling and blasting method, the explosive explosion will produce negative effects such as blasting vibration and shock waves; due to its shallow buried depth, the vibration phenomenon on the ground during the tunnel blasting excavation is particularly prominent; therefore, when formulating the construction plan of the drilling and blasting method , controlling the vibration effect produced by blasting construction has become the primary consideration, and we must try our best to control the negative impact of blasting construction on ground buildings; especially when there are important buildings and cultural relics on the ground, if they are not well controlled, there will be serious consequence

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