Simulation Of Dynamic Behaviors And Research On A New Automatic Erector

Shield technology is an advanced tunnel construction technology, which has been developed as the demand of modern underground engineering, mining and water conservancy projects.Compared with the other methods of excavation, shield technology has the advantages of faster excavation, higher security, lower costs, environment protection and lower labor intensity. As the kernel part of the shape assembling facilities and corollary equipment of shield machine, the erector of shield assembling facilities has only been imported and the core technology of shield technology been held by foreign manufacturers till now, so the localization of shield integration technology is of great significance.In this paper, a new automatic erector of six degree of freedom has been studied, and the dynamic characteristics of the machine were co-simulated by the use of the large-scale finite element software ANSYS and the multi-body dynamics simulation software ADAMS. According to the elementary structureal analysis and theoretical calcalation of the erector, the virtual model of erector has been established by the 3D software Solidworks, then through the interface between software Solidworks and ADAMS, the X_T format file of erector was imported to ADAMS. By studying the multi-rigid-body dynmaics of the erector, the dynmaics characteristic of it was simulated. Specially the speed of segment assembly was detailed simulated, results showed that the lifting cylinder should be adopted at a lower speed and small startup acceleration during segment grab and retraction stage, that maximum impact load occurred in segment rotation to 90 degrees position and that rotation speed of erector should be held less than 1rad/min, which provided safe and effective data for on-site construction. The calculated result from the above simulation was taken as the boundary condition in the finite element analysis of the key components, the strength and stiffness of the lifting cylinder and segment bridge have been calculated by ANSYS, and the modal analysis of the cylinder has been done and vibration characteristics (natural frequencies and mode shapes) been determined, so as to control the corresponding frequency of exciting force, avoid resonance under the vibration model, which provided further evidence for machine structure design. Finally, based on the field test of the erector, the performance parameters of erector and maximum impact load under different stretching speed, startup acceleration and circumferential rotation speed of the lifting cylinder have been measured. The field test data accorded with the virtual simulation data, verifying the feasibility and validity of the erector design theory and method.