Analysis On The Shield Segment Erector’s Structure And Study Of Dynamic Performance Simulation

This thesis is intended to design large-diameter suited serial-parallel mechanismsegment erector of six degrees of freedom through the structure classification andsummary of current shield segment erectors as well as the analysis of erection techniqueseventually to achieve the positioning of axial deformation, horizontal deformation andaxial rotation, three kinds of posture adjustments of deflection, pitch and rolling,automatic erection process of shield segments and a higher accuracy of segment erectionduring the shield segment erection process.The structure of segment erectors must meet requirements regarding being fit tosmall and narrow operating space, heavily loaded, high stability and rigidity of thestructure, fast response, flexible movement, high erection accuracy, matching with thetunneling speed etc. The lifting, revolution and translational motions of the erector areachieved by the serial position mechanism. The fine-tuning mechanism adopts4-SPS-1-Sparallel structure and the kinemics analysis of the segment erector’s fine-tuningmechanism and the building of the mechanism are performed.The three-dimensional structure model of the overall erector is built by Solidworkssoftware; relative motion states of all the parts and hinges are observed to inspect thesystem’s speed and acceleration features; whether any branch chain has any interferencethrough the kinematic simulation is checked; whether kinematic parameters of key partsmeet the design requirements is checked and finally adjustments are performed tostructures and materials according to the related results.Perform dynamic simulation and finite-element analysis on its key part–serial-parallel fine-tuning mechanism with ADAMS simulation software and ANSYSfinite-element analysis software to verify whether all performances and technicalindicators meet the design requirements and purpose of this segment erector, checkwhether the structural design is reasonable and whether meet the kinematic requirementson fine-tuning mechanism during the erection process. Simulate all the segment erector parts’ variation conditions of stresses during theshield operation and calculate all mechanism’s variation values of form and structurethrough the meshing and change of constraint conditions for the already built model ofshield segment erector fine-tuning mechanism in order to make better choices onmaterials of all mechanisms and space facilities arrangement by the ANSYS software andthe finite-element analysis method.