Abstract

Microseismic monitoring system is one of the effective means to monitor ground stress in deep mines. The accuracy and speed of microseismic signal identification directly affect the stability analysis in rock engineering. At present, manual identification, which heavily relies on manual experience, is widely used to classify microseismic events and blasts in the mines. To realize intelligent and accurate identification of microseismic events and blasts, a microseismic signal identification system based on machine learning was established in this work. The discrimination of microseismic events and blasts was established based on the machine learning framework. The microseismic monitoring data was used to optimize the parameters and validate the classification methods. Subsequently, ten machine learning algorithms were used as the preliminary algorithms of the learning layer, including the Decision Tree, Random Forest, Logistic Regression, SVM, KNN, GBDT, Naive Bayes, Bagging, AdaBoost, and MLP. Then, training set and test set, accounting for 50% of each data set, were prospectively examined, and the ACC, PPV, SEN, NPV, SPE, FAR and ROC curves were used as evaluation indexes. Finally, the performances of these machine learning algorithms in microseismic signal identification were evaluated with cross-validation methods. The results showed that the Logistic Regression classifier had the best performance in parameter identification, and the accuracy of cross-validation can reach more than 0.95. Random Forest, Decision Tree, and Naive Bayes also performed well in this data set. There were some differences in the accuracy of different classifiers in the training set, test set, and all data sets. To improve the accuracy of signal identification, the database of microseismic events and blasts should be expanded, to avoid the inaccurate data distribution caused by the small training set. Artificial intelligence identification methods, including Random Forest, Logistic Regression, Decision Tree, Naive Bayes, and AdaBoost algorithms, were applied to signal identification of the microseismic monitoring system in mines, and the identification results were consistent with the actual situation. In this way, the confusion caused by manual classification between microseismic events and blasts based on the characteristics of waveform signals is solved, and the required source parameters are easily obtained, which can ensure the accuracy and timeliness of microseismic events and blasts identification.

Highlights

  • The events collected by the microseismic monitoring system are classified into two categories: (1) microseismic events generated in the rock deformation and micro-crack expansion inside the rock mass [16]; and (2) blasts of rock mass caused by the impact wave directly generated by the underground dynamite explosion [17,18]

  • The study on microseismic signal identification can be roughly divided into spectrum analysis, statistical analysis, and artificial intelligence method involved in this paper

  • The results show that except for Logistic Regression, K-nearest neighbor (KNN), Naive Bayes, and Bagging algorithms, the recognition accuracy of other algorithms to the training set is 100%; the performance of Random Forest and KNN on the test set is better, reaching 94%, and the accuracy of Logistic Regression and Bagging algorithm can achieve 92%

Read more

Summary

Introduction

The process of micro-crack expansion in the rock mass is difficult to be captured by traditional rock mass stability monitoring technology. During the inelastic deformation process, the elastic potential energy accumulated inside the rock mass will be released in the form of a vibration wave [1,2], which will be received by the sensor arranged by the microseismic monitoring system and defined as a microseismic event. The events collected by the microseismic monitoring system are classified into two categories: (1) microseismic events generated in the rock deformation and micro-crack expansion inside the rock mass [16]; and (2) blasts of rock mass caused by the impact wave directly generated by the underground dynamite explosion [17,18]

Methods
Results
Discussion
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call