Dynamic Characteristic Analysis And Structure Parameters Optimization Of TBM Hydraulic Cylinder

Full-face hard rock tunnel boring machine (TBM) is a large tunnel construction equipment, used in hard rock geology. Strong vibration is prominent during the process of rock breaking and excavation, which has a significant impact on the dynamic characteristic of the thrust hydraulic cylinder. But the selection and design of TBM hydraulic cylinders usually rely on the theory of pressure and flow requirements, without considering the impact of foundation vibration at present. In order to explore the foundation vibration’s impact law on the asymmetric hydraulic cylinder, improve the dynamic characteristic, the propulsion performance, and complete the theory of selection and design of the hydraulic cylinder, the works carried out and responding conclusions of this paper are as follows:(1) The mathematical models of hydraulic cylinder dynamic characteristic with and without foundation vibration were built based on the theory of the annular gap flow and the correctness of dynamic mathematical model was experimentally verified.(2) The dynamic characteristic of the hydraulic cylinder with and without foundation vibration were comparatively analyzed, and variation law of dynamic characteristic under different axial foundation vibration parameters was acquired. Taking the pressure fluctuations amplitude of10%of the pressure value without foundation vibration as failure threshold value, the vibration amplitude-frequency region allowed by the hydraulic cylinder works properly was determined. And the selection criteria and process of hydraulic cylinder under axial foundation vibration was proposed.(3) Piston diameter, the length of the cavity, the piston width and gap height’s impact on the dynamic characteristic of the hydraulic cylinder under axial foundation vibration were analyzed using single factor analysis method. Taking pressure fluctuation amplitude, the largest oil leakage and piston rod work safety factor as the response value, the structural parameters of hydraulic cylinder were optimized based response surface methodology. The best combination of structural parameters was determined that multiple response values meet the engineering requirements at the same time. The vibration amplitude-frequency region that optimized hydraulic cylinder normally works is45%wider than before. And the design process of hydraulic cylinder under axial foundation vibration was proposed.