Research On Monitoring And Prediction Model Of Support Structure In Easily Damaged Areas Of Ore-penetrating Veins In Pulang Copper Min

A complete and reasonable monitoring system for support structures is an important means to study the stress and deformation of support structures,and to verify the support plan.The large amount of data obtained from monitoring can intuitively display the support status of underground support structures.In addition,using a reasonable mathematical model to predict monitoring data can effectively identify potential support problems and safety hazards.Through analysis and prediction of monitoring data,effective decision-making basis can be provided for mine managers,ensuring the sustained and stable development of the mine.The Diqing Pulang copper mine in Yunnan Province adopts natural caving method for mining,and the supporting structure of the ore-passing veins in the bottom structure is under complex geological and stress conditions,making it difficult for traditional support structure theory calculations to match the actual site conditions.In order to accurately understand the working status of support structures in mine production,evaluate the rationality of support structures,and complete the monitoring and early warning of support structures,this paper establishes a real-time monitoring system for the support structure of the Pulang copper mine ore-passing veins,and uses mathematical models based on monitoring data to complete the early warning analysis of the support structure of the bottom structure of the Pulang copper mine.Firstly,the construction of the support structure monitoring system was completed.By analyzing the numerical model of the FLAC^3Dbottom structure and investigating and analyzing the on-site damage of the easily damaged sections of the veins,the support structure construction and monitoring sections were determined,and the corresponding monitoring nodes for the support structure were designed.Subsequently,based on the support plan,the selection of monitoring equipment was completed,and an accurate,comprehensive and economical support structure monitoring system was established on this basis.Secondly,the monitoring data was preprocessed,and the evaluation of the effectiveness of the existing ore-passing support plan was completed through analysis of monitoring data.Based on the stress and strain changes of the support structure presented by the monitoring data and combined with the actual situation on-site,the reliability and effectiveness of the online monitoring system for support structures were verified.Finally,the paper used the autoregressive moving average（ARMA）model to predict the corresponding strain monitoring data.Since the ARMA model has the potential disadvantage of losing regularity information in the process of using difference processing for time series when dealing with non-stationary data,the prediction accuracy of the established ARMA model did not meet the requirements.On this basis,combined with the stress characteristics of the Pulang copper mine natural caving method ore-passing support structure,a Holt-Winters-ARMA combination model based on wavelet analysis was proposed.The monitoring data was decomposed into low-frequency and high-frequency sequences using wavelet analysis.The low-frequency sequence represents the static load borne by the support structure,reflecting the stress-strain trend of the support structure,and is modeled and predicted using the Holt-Winters model.The other high-frequency sequences of different frequencies represent the random disturbance load caused by large block collapse,blasting disturbance,and other factors during the ore-passing production process,which are detail signals in the original time series,and are modeled and predicted using the ARMA model.The predicted values of the two models were added to obtain the final combined model predicted value.By comparing with the corresponding real monitoring data,it was proved that the combination model had higher prediction accuracy for the support structure of the Pulang copper mine ore-passing veins,providing a more scientific prediction model for the early warning of support structures,and supplementing and improving the early warning module of the monitoring system for the support structure of the Pulang copper mine bottom structure.