Impact damage of flying gangue in steeply dipping seams and its control

Flying gangue has the characteristics of dynamic migration and enormous detriment. Reasonably con-trolling its damage is one of the prerequisites for the safe mining of steeply dipping coal seam. In this paper,based on the Kal-man filter principle,the dynamic characteristics of flying gangue were obtained,the mechanism of flying gangue haz-ards and the parameters of control element were studied,and a methodology about flying gangue damage control was proposed. The results show that when the flying gangue collides with facilities,its impact energy can be dissipated into various forms of energy,of which the deformation energy of the facility accounts for the largest amount. The impact en-ergy of flying gangue before collision and the recovery coefficient of impact energy of equipment jointly affect the de-gree of flying gangue energy-loss. Therefore,the flying gangue damage control can be started from two aspects,inclu-ding increasing the impact energy recovery coefficient of facilities and reducing the impact energy of flying gangue. Pa-rameters of the control element for working face in steeply dipping coal seam with large mining height were determined by LA-DYNA,the diameter of the polyester was 6 mm and the size of the diamond mesh was 100×100 mm. Then thecontrol element was applied in field,the number of casualties caused by flying gangue was reduced and the problem of short usage period was effectively improved.