Study On Stability Evaluation And Support Optimization Of Stope Roof In Chengchao Iron Mine

In the underground mining process of metal mines,a series of safety accidents often occur.Among them,roof accidents,as the most frequent accidents in various safety accidents,need to be carefully studied and analyzed.With the increase of mining depth,the western part of Chengchao Iron Mine has formed a complex geological condition in which the upper part is a filling body and a pillar,and the lower part is a caving mining method.Therefore,the roof stability of the stope under the complicated conditions is studied.Safe production is of great significance.The stability of the surrounding rock of the roof affects the choice of support scheme.The decision of support parameters affects the safe production and economic benefits of the mine.Therefore,it is necessary to optimize the support,balance the safety investment and economic income,and coordinate the promotion of the mine.Sustainable development.The paper analyzes the stability of the roof of Chengchao Iron Mine-500 m below the level,so as to select a reasonable support scheme and optimize the selected support scheme.The main research contents are as follows:First,analyze the disaster-causing factors of metal mine roof accidents,construct a Bayesian network model to predict the occurrence of roof accidents and the investigation of dangerous sources,and provide reference for mine roof management.Second,analyze the environmental factors of roof accidents.Under the condition,the fuzzy neural network evaluation model is constructed to evaluate the stability of the surrounding rock and provide the basis for the selection of the support scheme.Thirdly,the orthogonal experimental design is used to simulate the bolting and shotcreting support of the roadway,and the regression analysis is used to obtain the roadway branch.The functional relationship between decision-making indicators and support parameters,using multi-attribute utility theory to select optimal support parameters to achieve the purpose of support parameter optimization;Fourth,using various network models,optimization algorithms,computer software and other information technologies Specifically,the stability of the roof under special conditions of Chengchao Iron Mine is analyzed,and the support parameters are optimized and applied to the on-site production.The research results show that under the special working conditions of Chengchao Iron Mine,the roadway of the stope at the same level has better stress conditions in the lower part of the filling stop,and the stress level away from the lower part increases,and the local area may The stress concentration phenomenon appears.The fuzzy neural network is used to evaluate the stability grade of surrounding rock of each roadway roof is III(basic stability).The selected support scheme is anchor spray support,and the optimization of support parameters is selected at the roadway with the lowest average safety factor.Calculate,the optimal support parameters are: the length of the two bolts is 1.8m,the length of the arch bolt is 2.4m,the diameter of the bolt body is 16 mm,the spacing between the bolts is 0.4m,the spacing of the bolts is 0.4m,shotcrete The thickness is 160 mm,which meets the needs of safety and economy.The above research results have certain guiding significance for mine production.