Study On Bolting Fatigue And Work Break In Fully Mechanized Excavation Face

Anchor bolting is an important part of the excavation of coal mine roadway.During the support process of the fully mechanized mining face,the bolting workers are prone to various kinds of work fatigue,but there is no reasonable break system.By studying the bolting worker's work contents and the characteristics of bolting fatigue,the fuzzy mathematics method is used to comprehensively evaluate the level of the bolting work fatigue.Combined with a comprehensive evaluation model of support work fatigue based on physiological changes and mental states of bolting workers such as skeletal muscle and heart rate,and finally use Jack to build a reasonable rest break system.(1)The organization method and operation process of support operations were studied.Through the study of the support site environment and support procedures,the characteristics of mine support operations were clarified.The ergonomic factors affecting fatigue of bolting operations were: Duration,posture,and mental load.Based on the fatigue characteristics,10 fatigue indicators including arm soreness,neck soreness,shoulder and back pain,waist soreness,inattention,decreased accuracy,increased subjective task difficulty,decreased work enthusiasm,tiredness,and irritability index.(2)Use network analytic hierarchy process to determine the weight of each evaluation index,and a fuzzy comprehensive evaluation model for bolting work fatigue was constructed.Continuous heart rate measurement was performed on 20 bolting workers,and the heart rate change rate was found to be the largest at 77 minutes,which is the inflection point of fatigue time.Based on the revised fatigue value model.The fatigue value at 77 minutes was calculated to be 68.49.Based on this limit,according to the difficulty of the bolting task,the bolting workers themselves determined the occurrence the break time.(3)Use Jack software's MEE tool to analyze the metabolism of the bolting workers.When the bolting work reaches 77 minutes,in order to avoid fatigue accumulation,a 13 minutes' break should be taken and the best operation of anchor bolting when considering the relaxation time should be 22.5 minutes,which could provide a reference for the formulation of a reasonable rest break system.There are 34 figures,28 tables and 92 references in this thesis.