Study On Parameter Optimization Method Of Bench Blasting In Open Pit Mine

In the production practice of open-pit mine,blasting parameters are often improved to reduce the bulk rate,promote the process of mining,transportation and soil discharge,and finally save the cost.This paper starts with the improvement of blasting parameters,through the optimization of blasting parameters,better understand the effect of the change of parameters on the open-pit bench blasting,and then guide the blasting of the mine.This paper mainly carries out the following work:(1)Of different buried depth of rock core sampling,processed into standard specimens in the laboratory,using the United States production of MCT triaxial pressure testing machine,with several groups of sample triaxial experiments respectively,eac h group of cores with different confining pressure,confining pressure,presented in arithmetic progression,0 MPa,respectively,5 MPa,10 MPa,15 MPa,20 MPa,to guarantee the accuracy of the more rigorous,inserted between 7 MPa,12 MPa,17 MPa,eight groups of sample.The rock mechanics parameters of rock samples are obtained through experiments.Through the data statistics of these eight core groups,the rock mechanical parameters under the same geological conditions in this mining area are estimated: elastic modulus,poisson's ratio,internal friction Angle,etc.,providing data support for ANSYS simulation.(2)Describes the mining blasting effect of several kinds of evaluation methods,mainly using the analytic hierarchy process(ahp)to analyze the natural factors,namely,human factors of the perforation parameters,specific charge,tamping length,deep,according to the actual field experience,give different values,it is concluded that different weights,and transfer the optimal method of comparing with general analytic hierarchy process(ahp),it is concluded that the optimum method to avoid the transfer of the importance of these factors and advantage of the consistency check sorting: specific charge perforation parameter > > > filling length of super deep.(3)Based on the comparison between the actual situation on site and the empirical formula about the hole row distance,packing length and ultra-depth,the three groups of data that need to be simulated and optimized are obtained to provide the practical basis and data basis for the subsequent ANSYS analysis.(4)Focus on using ANSYS software to analyze the comparison of blasting effect in the case of different hole row spacing,filling length and over depth.Show the energy and blasting cloud pictures at different moments when the parameters change,so as to select the most suitable blasting parameter combination.(5)Based on the representative sample data of several blasting in this mine,a neural network model is established to predict the possible bulk rate generated by the optimized blasting parameter combination.(6)The best combination of parameters obtained by simulation is applied to mine blasting to observe the blasting effect,carry out picture comparison and statistics of block rate,and compare with the block situation predicted by neural network.The results show that the results are basically consistent.In addition,the analysis shows that the impact of blasting vibration on the surrounding buildings and the safe radius range of fl ying stones conform to the rules and standards.Practice has proved that the optimized blasting parameters can improve the blasting effect,reduce the bulk rate and have good guiding effect in the engineering practice of this mine.