Research status and development trend of borehole stemming in drilling and blasting method

Drilling and blasting is the main method of current rock excavation.When drilling and blasting method is working, the suitable stemming is compared to no stemming, which could improve the blasting effect by 10%-50%, the explosive unit consumption by more than 10%, the air shock wave pressure by 75%-80%, and the explosive gas to act on the explosive medium could extended by 3-5 times.The quality of the blasthole stemming is an important factor affecting the blasting effect of the drilling and blasting method.After more than 30 years of development, the research on blasthole stemming has made great progress.This paper analyzes the mechanism of stemming, the movement law of stemming, stemming length and stemming material.It is pointed out that the research on the mechanism of the blasting shock wave and the explosive gas is not clear.The formula for calculating the stemming length under different blasting has not been established, and there is no shortage of new stemming materials such as convenient and quick filling and good filling effect.It is proposed to replace the traditional detonation source with a new type of electric blasting device, research on new expansion stemming materials, and strengthen the cooperation between universities and blasting enterprises is the development trend of future stemming research.