Mechanism Design And Mechanical Characteristics Analysis Of A Series Of6m Subway Shield Segment Erector

Segment erector is one of the key subsystems of shield machine and its main function is to erect precast segments on the inner tunnel surface, and prevent the collapse of the tunnel. Reasonable structure design and good dynamic performance of the segment erector play an important role in the precise and rapid erecting of segments, which is of great practical significance for the improvement of the construction efficiency of shield as well as for the saving of construction energy. Therefore, researches are carried out in the following aspects:(1) The structure features of the existing segment erector is analyzed, a segment selection principle of the machine is established, and a6m-level subway shield segment erector structure program is proposed.(2) A kinematic model of the robot manipulator is built and inverse solutions of the five-bar mechanism and the fine-tuning mechanism position are analyzed, and a speed mapping model is derived. In view of the defects of the existing fine-tuning mechanism, a new kind of3-DOF rotating fine-tuning mechanism is designed by adopting the structure of unconstrained chains and passive constrained branched chains. Besides, the singularity of the new mechanism is discussed.(3) Based on the virtual prototype technology, a multi-body dynamics simulation analysis model of all-inclusive action process of the segment erector is established by utilizing the dynamics analytical software ADAMS. The erecting of segments at different positions is simulated and analyzed, and the mechanical behavior of the segment erector is studied.(4) Through the stress analysis of different components of the segment and erector under different working conditions, dangerous working conditions of such structures as the yoke and the trimmer beam are obtained. On this basis, the statics analysis of the segment erector is conducted, the strength and stiffness characteristics of its key components are studied, and finally experiments are employed to prove the correctness of the results of strength and stiffness analysis.