Method for evaluating degree of blasting damage of surrounding rock in underground water-sealed cavern

Abstract

The invention relates to a method for evaluating the degree of blasting damage of surrounding rock in an underground water-sealed cavern. A set of blasting vibration monitoring points is arranged behind the tunnel face; the naked rock excavated in the excavation is classified based on the Q classification method, and the equivalent rock mass A value of a group of monitoring points is obtained through formula conversion; the law of propagation of surrounding rock vibration is obtained by correcting and fitting the Sadowssky formula using the maximum single-section charge amount, the distance from the burst center, the combined peak speed and the A value of one blasting; the prediction value of the combined peak vibration speed is obtained based on the law formula of propagation of surrounding rock vibration and follow-up blasting parameters and the Ai value of each monitoring point, and is compared with the measured value to obtain the vibration speed reduction rate of each monitoring point, and the arithmetic mean value is taken as the degree of blasting damage of surrounding rock. The method takes into consideration the influence of the rock mass on the propagation of surrounding rock blasting vibration. It is reasonable and reliable to use the arithmetical mean value of the combined peak vibration speed reduction rate of each monitoring point as the evaluation index of the damage degree of the surrounding rock.

Description

technical field [0001] The invention relates to the field of damage evaluation of surrounding rocks of underground engineering under the action of blasting excavation, in particular to a method for evaluating the damage degree of surrounding rocks of underground water-sealed caverns by blasting. Background technique [0002] The underground water-sealed cavern is to store energy (petroleum, liquefied petroleum gas, etc.) in a certain volume of rock cavity by using the pressure sealing effect of groundwater. Most of them use high side walls and large-span underground caverns, and the drilling and blasting method is used during the construction period. Excavation, its operation is in a dynamic groundwater environment for a long time. As the main form of future oil and gas energy storage in my country, underground water-sealed caverns have the advantages of safety, environmental protection, cost saving and land saving. [0003] The blasting excavation of underground water-seal...

AI Technical Summary

Problems solved by technology

However, in the actual operation process, the acoustic wave velocity detection method needs to construct more drilling holes, and the detection range is small, which will consume a lot of time and money

[0004] At present, there is still a lack of evaluation indicators and evaluation methods for the blasting damage of the surrounding rock of underground water-sealed caverns.

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