Study On Slope Stability Of Deep Part Bench Blasting Vibration In Open Pit Mine

The main production method of the open-pit mine is to use blasting to break the rock,and the vibration caused by blasting will affect the stability of the slope.And as open-pit mines with long mining years have continuously entered the deep recessed mining stage in recent years,the number of high and steep slopes has also been increasing.The strong blasting vibration makes high-steep slopes with poor stability more prone to disasters such as collapses and landslides,causing irreparable losses.This paper takes the blasting vibration of a deep-pit mining open-pit mine in Inner Mongolia as the engineering research background,and adopts the method of blasting vibration field measurement analysis and high-steep slope static load and dynamic load numerical simulation analysis method for the high-steep slope of the mine.Comprehensive analysis of the stability under the action of blasting vibration.Use the model to simulate blasting vibration,provide corresponding scientific basis for safe mining of mines,and provide cases for analyzing the stability of high and steep slopes in other deep-pit open-pit mines.By consulting the geological data of the open-pit mine,master the engineering geology and hydrogeology of the mine's slope.On this basis,the high and steep slope stepped rock of the open-pit mine is collected as the test material,and the indoor petrophysical property experiment is carried out to accurately determine the rock mechanical parameter properties of the mine;the natural discontinuous surface shear test innovatively uses rock The 3D printing technology improves the reliability of the experimental determination of the mechanical properties of the discontinuous surface.The experimental results prove that the rock mechanics strength of the high and steep slope on the south side of the open-pit mine is relatively high,the number of structural weak surfaces such as faults is small,and the overall slope rock mass stability is good.The mine's boundary blasting and bench blasting vibrations were monitored many times on site,and the maximum peak vibration velocities of boundary blasting and bench blasting obtained from each actual measurement were fitted using the least square method to obtain the boundary blasting and bench blasting of the corresponding slope.Sadowski blasting vibration velocity attenuation equations in horizontal radial,horizontal tangential and vertical directions;and based on the blasting vibration safety allowable particle vibration velocity,the maximum single-stage explosive charge for pre-split blasting and step blasting is obtained,which is the safety of the mine Provide basis for production.The method of numerical simulation is used to verify and analyze the slope stability.The slope model was constructed after corresponding simplification of the geological section map of the south bank.The slope stability analysis is carried out under the conditions of static load and blasting dynamic load respectively.Under the weight of the high and steep slope model,analyze the stress and strain distribution of the slope,the distribution of the plastic zone,the displacement in the vertical and horizontal directions,etc.,and find the position where the maximum displacement occurs;adopt the slope strength The reduction method is used to solve the safety factor of the slope model.The results show that the south slope has good stability under its own weight,and the safety factor is about 1.2.The displacement of the simulated slip zone through the slope is relatively small,about 3.5 cm.Under the dynamic condition of blasting equivalent triangular load,this side The speed of each monitoring point on the slope is less than the maximum peak vibration speed allowed by safety.The dynamic load simulation of high and steep slopes is discussed,and the blasting equivalent triangular load is applied to the slope model after strength reduction.Under this dynamic condition,the stress distribution and displacement of the slope and the velocity and acceleration distribution of each monitoring point were analyzed again,and it was found that the slope displacement continued to increase,and the cyclic degradation of the blasting dynamic load on the slope was obtained.It is concluded that the action of stress and inertial force reduces the anti-sliding force of the slope and thus the stability of the slope.