Simulation Analysis Of The Coal Releasing Process Characteristics And The Coupling Characteristics Between The ZF15000/28/52 Top-coal Caving Hydraulic Support And The Surrounding Rocks

Top caving hydraulic support is one of the key techniques in fully mechanized mining,the support is classified into two types:the four-column positive four-link low-level support and the four-column inverse four-link low-level support,and the dynamics coupling relationship between the top caving hydraulic support and the surrounding rock is the main research.Based on the project "Four-link supper power top caving hydraulic support research" of the 863 Program(number:2012AA06AA407),the dynamics coupling relationship between the ZF15000/28/52 export-type four-column positive four-link low-level top caving hydraulic support and the surrounding rock is researched and the top caving process is simulated.The movement trend of the coal particles during the working process of the top caving hydraulic support is simulated by using the coal crush model established by EDEM software,and the law of the top coal crush,the broken laws of the direct top and the fundamental top are obtained.The mechanical system model including the fully mechanized mining hydraulic support and the surrounding rock is established,the coupling virtual model including the ZF15000/28/52 top caving hydraulic support and the surrounding rock is set up by employing Pro/E software according to the mechanical model and the mining parameters.The model is imported into a dynamics simulation software,the dynamics simulation of a working cycle is performed,and the stress conditions of the top beam,the first-stage cylinder and the second-stage cylinder of the column,and the shield beam of the top caving hydraulic support are obtained.The model of the top caving hydraulic support is meshed by using ANSYS software,and the model of the surrounding rock is meshed by using Recurdyn software.The dynamics simulation of a working cycle to simulate the rigid-flexible coupling model between the top caving hydraulic support and the surrounding rock is performed,and the stress conditions of the middle beam,the first-stage column,the second cylinder are obtained,the simulation results of multi rigid body coupling are compared and analyzed.Finally,the fatigue strength analysis of the top caving hydraulic support is performed by using ansys workbench,and the lifetime predictions of the top beam,the base,the tail beam and the column are carried out according to the research results.The research results obtained in this paper can provide basis for strength analysis,structural optimization and time control of caving coal hydraulic support.