Research On Long Hole Loosen Blasting Technology For Bottom Floor Rock Of Fully-mechanized Face In Coal Seam

This paper study the long hole loosen blasting technology for bottom floor rock of fully-mechanized face in coal seam based on theoretical analysis, such as Explosive Mechanics, Rock Mechanics and Damage Mechanics etc, and what's more, the commercial testing in status quo has verified it.First of all, the paper describes in the mechanical feature of rock under explosive load, including stress, deformation, intensity, dynamic stress field and so on. At the same time, some constitutive models of dynamic response within rock in the process of blasting have been analyzed comparatively. And these are all the basis of the long hole loosen blasting technology.From the role of explosion stress waves and gas from explosion, the process of loosen blasting, laws of crack propagation and characteristics of loosen blasting funnel are analyzed systemly. Through explosion waves and explosion stress waves in the beginning of rock's rupture stage is very important, the relationship of the development of the Loosening wedge fracture and the quasi-static stress field produced by gas from explosion is inseparable.In order to loose rock effectively, reduce the rate of large rock and improve the utilization of blasting energy at the same time, the paper have been put forward theoretical methods for design and optimization of parameters (charge of borehole, depth of borehole, ultimate burden, density of borehole, construction of charge, stemming of borehole and so on) of the long hole loosen blasting for bottom floor rock of fully-mechanized face in coal. Commercial test in Liuzhuang coal mine has been proceeded, which define the actual blasting scheme and factors of the long hole loosen blasting for bottom floor rock of fully-mechanized face in coal seam, and good results has been got.According to fuzzy math theory, combining comprehensive evaluation method, quantitative effects of this long hole loosen blasting is evaluated systemly, which is a more reasonable to the practice in status quo.Therefore,the achievements of this thesis can be a good reference for execution of the long hole loosen blasting.