| Due to the frequent occurrence of rock burst in roadway in recent years,unit support,as the main support equipment of underground roadway,plays a role in supporting roadway roof and floor and maintaining the safety of workers.In order to prevent the occurrence of rockburst accidents and realize the efficient and safe production of coal mine,this paper creates a new type of unit support roof beam based on the original simple structure of the support for the complex working conditions of rockburst.The three-dimensional model of the whole unit support was constructed,and the modal analysis of the whole unit support was carried out.Statics strength analysis and fatigue strength analysis were carried out on the whole bracket,and the overall strength and life of the bracket were checked.ANSYS and Adams software were used to create rigid-flexible coupling model of the unit support,and the dynamic response of the support under impact load was analyzed.A mechanical-hydraulic co-simulation model was established to investigate the impact on the dynamic characteristics of the support hydraulic system.Research on support characteristics of unit hydraulic support under different impact conditions to understand support characteristics;The dynamic characteristics under different impact loads are obtained,which lays a foundation for the realization of downhole automation and intelligent production.The main research contents are as follows:(1)In order to avoid the influence of anchor rod and cable on the top beam of the support,a new type of unit support top beam structure was created,a three-dimensional model of the unit support was established,and the model was simplified and combined.The finite element model of the support was created,and the modal analysis of the whole unit support was carried out,and the modal shape diagram of each step of the support was obtained.The maximum deformation appeared in the second order,which was 1.8952 mm.The results showed that the unit support was less affected by rock burst vibration,and the dynamic characteristics of the unit support structure system were stable;(2)By adding different load conditions to the unit support and calculating the statics strength of the support,the stress and deformation cloud map of each component and each state of the unit support were obtained.After removing the stress concentration,the maximum stress under the four kinds of loading was 449.47 MPa,which did not exceed the yield strength of the material,and the support met the strength design requirements.Through the simulation of alternating load applied to the support,the fatigue life of the whole unit support and the dangerous parts was obtained.The cycle load times that the unit support can bear can be up to 106 times,which can meet the support requirements;(3)The rigid body virtual prototype model of the unit support was established by Adams,the Apdl module in ANSYS was used to generate the neutral file of the flexible body of the top beam of the support,and the rigid-flexible coupling simulation model of the unit support was established.Based on the contact and collision theory,the dynamic characteristics of the unit bracket under different impact effects were investigated.When the impact velocity increases gradually,the maximum stress of the support during the impact process increases gradually,causing damage.The fluctuation of the supported reaction force at the socket of the support increases with the increase of the impact energy,which is mainly caused by the vibration of the hydraulic system;(4)AMESim/HCD module is used to establish the hydraulic system model,and the system parameters are set.The Adams mechanical structure model and AMESim hydraulic system model are co-simulated through the interface,and the co-simulation results are analyzed,and some parameters affecting the dynamic characteristics of the unit support are analyzed.At the same time,the feasibility and accuracy of the co-simulation to study the overall dynamic characteristics of the scaffold are proved.There are 84 figures,6 tables and 75 references in this paper. |
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