Experimental Study On Influence Of Low-frequency Vibration On Radon Exhalation From Hyperthermal Deep Porous Emanium Medium

The approximate fifty years uranium mining,exhaustion of shallow reservation and development of nuclear industry promotion,the exploitation of deep uranium wells is an urgent issue.Scholars at home and abroad have conducted numerous researches on the pollution of uranium mining and metallurgical based on the occupational health and environmental protection demand of deep uranium mine workers.However,there are few studies on the phenomenon that the high mining ground temperature,high ground compression stress and low-frequency disturbances lead to a large number of secondary fractures in the uranium rock mass and the occurrence of abnormal exhalation of uranium rock surface.A test simulation device by radon exhalation under low-frequency vibration was designed and manufactured based on the analysis of the impact factors of the radon migration regularity in the roadway of deep uranium mine,the project of China National Science Foundation called ‘The study of the three difference coupling mechanism of deep uranium mine radon exhalation and radon airflow calculation mode’ and reference at home and abroad for inspective regulation of deep uranium mining and the treatment of radon exhalation by porous media under low-frequency vibration.The regulation of rock radon exhalation and pores and rock damages in uranium mine are studied through theoretical analysis,experimental research and numerical simulation methods.The main research contents and results are as follows:(1)Research & Development and Preparation of similar materials.The orthogonal experimental group was designed to prepare samples of uranium-like rock according to similarity theory.Simultaneously,the experimental group closed to the prototype was selected by doing physical and mechanical tests.(2)Research & Development of simulated test device under the low-frequency vibration.The test simulation device by radon exhalation under low-frequency vibration was developed based on the analysis of the migration mechanism of radon during the deep uranium mining process,which can simulate the phenomenon of radon exhalation in different emanating media and geological environments under different vibration frequencies and temperatures.(3)Experimental study of radon exhalation in deep uranium mine rock.The experimental device was studied the regulation of radon exhalation on uranium-like samples with different ratios during the deep mining operation,and an orthogonal design experiment was designed under coupling conditions.The mathematical analysis of cumulative radon concentration and exhalation rate has been done based on the experimental data to obtain the influences and degrees of different temperatures and vibration frequencies corresponding to different depths on the radon exhalation rate.(4)Experimental study of low-frequency vibration and rock sample fracture.Different ratios of samples were evaluated quantitatively used the ultrasonic sound detector,and the mechanism of rock fracture caused by the low-frequency disturbance was studied combined with the change of the porosity of the sample.