Study On Rockburst Tendency Warning And Acoustic Emissionlocation Technology

With the rapid development of the social economy,China has continued to increase the development and construction scale in the fields of transportation,mining and other fields,including various large rock construction projects.The number of underground rock engineering construction and complex geological conditions lead to frequent geological disasters,hindered the scheduled delivery of projects,and even caused more serious consequences such as casualties and damage to large construction equipment.As a rock mass instability phenomenon,rockburst is a frequent geological disaster in underground rock engineering,which can cause deformation of the excavation engineering structure and even cause local earthquakes.In order to ensure the safety of personnel and equipment during the construction process,it is necessary to evaluate the stability of the rock mass and predict the location of potential hazards.The main research content of this paper is divided into two parts.One part is to evaluate the rock mass with the rockburst grade as the identification framework,and the other is the location of the hidden hazards based on the assessment results,and reasonably evaluate and early warning the rockburst from the whole to the locality.The specific research content is as follows:1.In light of this geological disaster of rock burst,this paper comprehensively considers the mechanism of rock burst and the existing discrimination basis,and reasonably selects the evaluation index.The previous rockburst historical data was sampled and discretized using the five-factor method.Based on the sample data set demonstrated by the experts,the incomplete sample information is predicted and optimized by the gradient descent method.2.The NETICA software is used to perform statistical training on the existing sample information,obtain the probability distribution among the nodes,and construct a rockburst tendency alert model based on Bayesian network.The rockburst grade is used as the target node to conduct an overall assessment of underground rock engineering,and the sensitivity of each criterion node and target node is analyzed and ranked.Then the model was applied to the concrete rock burst cases and verified in the case of complete and missing data sets to obtain more reasonable evaluation results.3.According to the acoustic emission signal positioning theory and method,a portable signal acquisition and positioning system based on STM32 is designed.The system is mainly responsible for the collection and transmission of signals.After the data information arrives at the upper computer,the signal is denoised by the wavelet analysis using MATLAB.Next,a full-phase analysis method is used to perform spectrum analysis on the denoised signal,and a phase difference is used to obtain the time difference between the signals.Finally,the time difference is combined with the quad-probe square positioning method to realize coordinate positioning of the emission source.The experimental results show that 90.6% of the system positioning error is within 1.5cm,showing good accuracy and stability.