| With the continuous increase of coal mining intensity and depth,rock burst accidents occur frequently in coal mines,so it is an urgent problem for Chinese researchers to improve the anti-impact performance of underground hydraulic support.If the energy-absorbing components are installed in one end of the hydraulic columns,they will be changed from rigid support to rigid-flexible coupling support,which can improve the impact resistance of the support.The energy-absorbing components are the key element to improve the impact resistance performance for anti-impact hydraulic support.The ideal energy-absorbing components should have the characteristic of constant deformation resistance.At present,the energy-absorbing components applied in the mining field are mainly folding lines components.The folding lines energy-absorbing components have stable and repeatable buckling deformation mode,but the deformation resistance-displacement curve is approximately “W” shape,and can't achieve the ideal energy absorption effect.Therefore,it is urgent to find an ideal energy-absorbing component with constant deformation resistance.In this paper,the straight corrugated tube eversing components with constant resistance deformation were presented and studied.In this paper,based on the deformation work principle,the eversing deformation resistance of straight corrugated tube components was studied.The formula on calculating eversing deformation resistance of straight corrugated tube was obtained,and the results show the round angle radius,the wall thickness,the corrugated quantity and the corrugated radius are the important factors of influencing the deformation resistance.The round angle radius,the wall thickness,the corrugated quantity and the corrugated radius of the influence law for deformation resistance were further analyzed by the Matlab software.Deform-3D finite element software was applied to simulate and analyze the straight corrugated tube eversing deformating process under axial loading.The whole process of straight corrugated tube eversing deformating was obtained.The results show the resistance-displacement curve is approximately a level line,and absorption energy increases linearly,and the simulated deformation resistance value is close to the theoretical calculation value,and the influence of the round angle radius,the wall thickness,the corrugated quantity and the corrugated radius on the deformation resistance is the same as the theoretical analysis results.The simulation results also show two failure deformation forms,and that includes axisymmetric buckling deformation and tube end tearing.Based on Hill theory,the critical strain value of non-tearing at the tube end was analyzed.Based on the principle of buckling deformation under axial load on the slender rods fixed at both ends,the critical load ofthe straight corrugated tube without buckling deformation in the process of eversion was analyzed.Taking the straight corrugated tube material saving as the optimization objective,taking the straight corrugated tube deformation process not failing and meeting the use requirements as the constraint conditions,taking the Matlab genetic algorithm optimization toolbox as the tool,the straight corrugated tube size parameters of the multi-parameter global optimization was researched.Finally,taking the model of ZHD6000 gate type hydraulic support as an example,according to the optimization method of genetic algorithm,the size parameters of the straight corrugated tube which can be used for this type of support were designed,and the feasibility of the scheme was verified by finite element simulation. |
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