既有临空面对采空区上覆岩体爆破振速场的影响研究

作者:Zhou Jun-Ru; An Wen; Zhong Dong-Wang; Lu Wen-Bo; Wu Liang; Leng Zhen-Dong
来源:Blasting, 2021, 38(1): 21-27and86.
DOI:10.3963/j.issn.1001-487X.2021.01.004

摘要

Blasting seismic effect in overlying stratum is influenced by the boundary condition of underground goaf. By theoretical analysis and numerical simulation,the propagation mechanism of blasting seismic wave and spatial distribution of vibration velocity field were investigated under different boundary conditions. A criterion for influential partitions of blasting vibration was proposed according to the basic theories of propagation and attenuation of blasting vibration field. Results proved that the propagation path of blasting seismic waves was influenced by the free surface of underground goaf,and the blasting seismic effect was significant declined by the wave-path inflection point. The number of inflection points was a key factor for partitions of surrounding rock mass. The existence of ground surface had free surface effect on the overlying goaf stratum,which resulted in a magnification of blasting seismic effect on overlying rock mass. Considering the interaction between free surface of goaf and ground surface on wave propagation,the overlying stratum can be divided into two zones: Zone I is a magnified blasting vibration field and Zone Ⅱ is a weak-attenuated blasting vibration field. The proposed criterion has a guiding significance for blasting hazard control and blasting design optimization. ? 2022 Blasting.

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