Study On Dynamics For Safeguard Structures Of Coal Mine Movable Rescue Chamber And Refuge Chamber

The coal mine emergency refuge system is an organic whole composed of thefacilities, equipments and measures which can provide life support for persons in distresswhen an emergency occurs in the coal mine. In order to increase the survival chances ofthe coal mine underground staff, improve the efficiency of the mine rescue work andreduce the death rate per million ton of China, this dissertation discussed the compositionof the coal mine emergency refuge system and the layout optimization of emergencyfacilities. And the dynamic response and buckling of safeguard structures subjected to coalmine gas and dust explosion impact was studied. The results have important implicationson improving explosion impact resistance of the stiffened plate and shell structure.First the propagation mechanism of the coal mine gas and dust explosion was studied.The loads the safeguard structures suffered were simulated with the software FLUENT,and the influence of the angles between emergency facilities and roadways and thedistances between emergency facilities and the explosion point on the loads the safeguardstructures suffered was discussed. Furthermore, the simplified fixed equation of thepressure load that the safeguard structures suffered in the coal mine gas and dust explosionwas obtained.After that, because the stiffened rectangular plate was usually adopted in theblast airtight doors of coal mine refuge chambers, the discrete model was established basedon the stiffened rectangular plate subjected to the coal mine gas and dust explosion, and itsdynamic response was discussed. Furthermore, the nonlinear dynamic buckling of thestiffened rectangular plate with initial defect subjected to coal mine gas and dust explosionimpact was studied, and the influence parameters of the dynamic response and buckling ofthe stiffened rectangular plate were analyzed through the particular calculation. In order tooptimize the geometric sizes of plate and stiffener, the optimization model of the stiffenedrectangular plate was established with the software ANSYS. The correspondingoptimization results indicated that the critical buckling load of the stiffened rectangularplate could be improved by about50%than that of the volumetric bare board due to theappropriate density of longitudinal and transverse stiffeners and a suitable2.5:1aspectratio of the stiffener.Next, in allusion to the stiffened cylindrical shell subjected to the coal mine gas anddust explosion, its buckling under uniform axial compression was studied in the linearelastic range based on orthogonal anisotropic shell theory. The basic buckling equation ofthe stiffened cylindrical shell under uniform was deduced by using a Donnell function. Then considering large deflection, the dynamic response of the stiffened cylindrical shellwith pined-pined constraints under axial and radial associated impact was studied based onthe discrete stiffened shell model. Furthermore, the nonlinear dynamic buckling of thestiffened shell with initial defect subjected to coal mine gas and dust explosion impact wasdiscussed. And the influence parameters of the dynamic response and buckling of thestiffened cylindrical shell, such as initial defect, stiffeners, load time and thickness of shell,were analyzed through the particular calculation. In order to optimize the geometric sizesof plate and stiffener, the optimization model which assigned the axial critical bucklingload as the optimizing objective in keeping radial shock pressure under a constant wasestablished with the software ANSYS. The optimization results have importantimplications on improving explosion impact resistance of the stiffened shell structure.Finally, this dissertation discussed the construction design of coal mine emergencyfacilities for the Nalin Temple Mine at Jungar Banner, Ordos, Inner Mongolia AutonomousRegion. The detailed layout programming of the emergency facilities was designed basedon the actual situation of the mine. Furthermore, the blast airtight doors of coal minerefuge chambers and the shell of movable rescue chambers were devised. And it wasproved by simulations and explosion tests that the designs could meet theexplosion-resistant requirement.