• BLASTING
  • Vol. 40, Issue 1, 77 (2023)
FU Peng
Author Affiliations
  • [in Chinese]
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    Abstract

    As a discontinuous and anisotropic heterogeneous structure,rock mass is randomly distributed with joints,cracks,faults and other structural planes.The existence of structural planes has an important influence on blasting effect.In order to explore the influence of the angles and locations of structural planes on bench blasting effect,LSDyna numerical simulation and field experiments were conducted based on Beskuduk open pit coal mine.The numerical simulation results show that when the dip of the structural plane is less than 30 degrees,the peak stress is less affected.When the dip of the structural plane is greater than 30 degrees,the initial peak value of the explosion stress wave increases with the increase of the angle.In addition,the position of a weak interlayer in a bench affects the energy release.Compared to the situation that the weak interlayers are located in the upper area of the bench,the blasting effect when the weak interlayers are located in the middle and lower areas,the energy release is more obvious with a worse blasting effect,therefore a specific blast method is needed to solve the problem.The field practice shows that with the increase of the structural plane angle,the boulder yield presents a decreasing trend.For the situation that the weak interlayers are located in the middle and lower part of the bench,the method of increasing the subdrilling to 0.5 m and adding 3~5 m depth to the inclined holes can effectively reduce the boulder yield,improve the blasting effect and the shovel loading efficiency.