Abstract:
In order to accurately study the influence of horizontal bedding rock strata on the propagation of blasting vibration, a dedicated attenuation model for Hequ Open-pit Mine is established. This research focuses on the unique geology of "horizontal bedding rock strata+medium differences inside and outside the stope", sets up 15 measuring points inside the stope (rock strata) and outside (soil) to collect three-dimensional vibration data at a blasting center distance of 50-500 m. The bedding direction weighting factor
η is introduced to modify Sadovsky formula, quantify the influence of bedding on vibration directionality, and construct a model combining with linear regression. The results indicate that the peak vibration velocity in the vertical direction is the highest, which accords with the "Blasting Safety Regulations"; The resultant velocity of rock strata inside the stope is
K=201.30 and
α=1.30, while the resultant velocity of soil outside the stope is
K=225.60 and
α=1.42. The bedding reduces vibration attenuation by 8.5%. By clarifying the propagation mechanism of blasting vibration in horizontal bedding rock strata, a geological-working condition dual adaptive attenuation model is constructed. This model verifies the applicability of Sadovsky formula in complex geology, which can guide the optimization of unit explosive consumption in this mine and provide significant reference for the blasting safety in similar horizontal beeding open-pit mines.