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In the process of shield tunneling, the cutter will inevitably be worn and damaged and will need to be replaced frequently. The low efficiency and high safety risk of traditional manual cutter change have prompted robotic cutter change to become the mainstream trend of current research. However, it is difficult to realize mechanical automation disassembly due to the existence of many fragmented parts and complex disassembly steps in the traditional cutter system. Therefore, this paper proposes an eccentric integrated cutter system, which greatly simplifies the disassembly process while retaining the excellent fastening structure of the traditional cutter system. The evaluation system of the cutter system was established through the analytic hierarchy process, and it was verified that the eccentric integrated cutter system has obvious superiority in realizing automated disassembly and assembly and, at the same time, that it has good structural strength. Finally, vibration experiments were carried out based on shield construction conditions. The experimental results show that after 14 h of continuous vibration, the residual preload ratio of the integrated cutter sample stabilized at more than 90%, which indicates good anti-loosening performance. [ABSTRACT FROM AUTHOR]

Structural damage can affect the long-term operation of equipment. Real-time damage warning for structures can effectively avoid accidents caused by structural damage. In this paper, a real-time warning method of structural plastic damage based on the cointegration theory is proposed. This method calculates the cointegration relationship between the strain signals at different measuring points, and the stability of the strain signal relationships is also evaluated. The problem of inaccurate detection caused by the error of strain measurement and environmental influence can be eliminated by the comprehensive judgment of strain between asymmetrical measuring points. A real-time damage sensing system is developed in this paper. In order to improve the real-time and practicability of the system, this paper proposes and determines the residual warning coefficient by analyzing the proportion of the strain residuals exceeding the residual threshold. The research on this sensing system has certain value for the engineering application of damage monitoring methods. [ABSTRACT FROM AUTHOR]

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