Influence range simulation of loose blasting borehole in the coal-rock mass

摘要

The influence scope of the blasting borehole is the key factor to the construction of loose blasting measures. A non-linear numerical model considering the multi-physical coupling factors, including in-situ stress, coal damage, and gas migration, etc., is established, and the model is solved by Comsol Multiphyscics software. The influence range of gas migration is analyzed, and the influence scope is determined to be between 3.5 m and 4.0 m. The change law of gas concentration and gas volume in test boreholes around blasting boreholes are investigated, and the effective influence range of loose blasting is about between 3.5 m and 4.0 m. The consistency between field test and numerical simulation results show that the effective influence range of loose blasting can be regard as about 3.5 m. The conclusions of this study provide an effective solution for improving the effect of loose blasting as a local anti-penetration measure and determining the reasonable parameter of hole placement.