Study On Work Fatigue And Reasonable Shift Work Modes In Fully Mechanized Excavation Face

As the largest primary energy source in China,the safety and efficiency of coal production have been paid close attention.As an important production space of coal mine,fully mechanized excavation face has narrow space,harsh environment and many dangerous sources.Under the “three-eight system” shift work mode,the miners work long,high work intensity and serious fatigue accumulation,which has a great impact on the physical and mental health of miners.Through analysis of the work characteristics of fully mechanized excavation face,the characteristics of fatigue and recovery,and the characteristics of "three-eight system" shift mode,the subjective scale questionnaire method and the objective experimental method are used to measure the fatigue and recovery time of the miners in 15404 fully mechanized excavation face of Xindadi Mine.The subjective and objective recovery time prediction model is established,and the reasonable shift work mode is determined according to the fatigue complete recovery time and the shift rules.(1)The work characteristics of fully mechanized excavation face are analyzed from three aspects,including work environment,process flow and man-machine work.According to the work characteristics of fully mechanized excavation face,the influence factors of miners fatigue are analyzed from five aspects,including work intensity,environmental conditions,work rhythm,bodily functions and nutritional sleep.And analyzed the "three-eight system" shift work schedule and cycle work diagram.(2)Based on the subjective questionnaire survey of 117 miners in the fully mechanized excavation team of Xindadi Mine,it is found that the morning shift miners feel extremely tired after six hours,the middle shift miners feel extremely tired after five hours,and the night shift miners feel extremely tired within the first four hours.In the three shifts,the RPE score of the support workers is the highest compared with other types of work.Flash fusion frequency meter and acousto-optic reaction time tester are used to measure the critical flicker fusion,reaction time and number of errors of fifteen support workers in three shifts before and after work.The results show that there is no significant difference in critical flicker fusion under green light state,reaction time and number of errors of support workers in early shift.but there is significant difference in the critical flicker fusion under red light state.There are significant differences in critical flicker fusion,reaction time and number of errors of support workers before and after night shift and middle shift.(3)The heart rate method is used to measure the recovery time of work fatigue of five support workers after morning shift,middle shift and night shift,and the prediction model of subjective and objective recovery time are established.The average objective recovery time of support workers is 18.10 hours and the average subjective recovery time is 17.07 hours.According to the fatigue complete recovery time and shift rules,this thesis analyzes the feasibility of the improved "Four-six system" and "Twoseven-one-six system" from five aspects,including work time,number of workers,employee satisfaction,public opinion and national policy,and suggests that the Xindadi Mine should adopt "Four-six system" shift work mode at the present stage.