Author(s)

Renliang Shan, Yongwei Song, Chi Meng, Pengcheng Huang, Mengnan Wang and Shupeng Zhang

Corresponding Author

Yongwei Song

ABSTRACT

In order to study the cumulative damage law of new shotcrete caused by tunnel blasting, the equivalent charge weight, equivalent distance and acoustic velocity of multiple blasting were statistically analyzed. It is found that the cumulative damage of shotcrete caused by blasting increases gradually with the increase of the number of cycles. After 4 cyclic blasting, the cumulative damage of No.1 measuring point near the explosion source is the largest, 0.274, which is greater than 0.19 of the standard damage threshold, but there is no instability failure of the shotcrete. When the distance between the measured point and the construction face is about 20 m, the cumulative damage is about 0.05, the vibration velocity and the damage inflection point appear. There is a good power function correlation between damage increment and vibration velocity.

KEYWORDS

Shotcrete, damage, blasting