Abstract:
To solve the problems of shield machine instability and excessive shield posture deviations caused by the lack of thrust force, a closed-loop control technology of the thrust cylinder pressures based on the target total thrust vector was proposed. Two thrust force vector calculation methods regarding to the shield driving with free partition technology of full-cylinders and the shield driving with self-compensation of missing thrust force were established,and the feasibility of both two methods were verified by constructing a large-scale model test platform, the testing results show that although affected by the performance of the proportional reducing valves during the two driving tests,oil pressure delays were found at the moment when the target pressures of the thrust cylinders changed, the measured pressures were controlled within ± 4% of the target values generally, and the total thrust force vector was maintained stable; the driving speed and shield postures were well controlled in the driving test with free partition of fullcylinders, while the acceleration phenomenon of the shield machine was discovered induced by the fixed flow output of the propulsion pump once part of hydro-cylinders were retracted, and sudden changes of the shield postures were caused at the same time by the response delay of the oil pressures and the uneven flow supply from the propulsion pump, both the driving speed and shield postures returned to the initial values after entering the full-cylinder thrust state; in the whole process of the driving test with self-compensation of missing thrust force, the shield driving speed and the shield posture deviations were controlled within ± 3 mm/min and -6 ~ +4 mm related to their respective ini? tial values
ZHU Yeting1,
2 GONG Wei1,
2 QIN Yuan1 etc
.Closed-loop Control Technology of Shield Thrust Hydro-cylinder Pressure Based on Target Total Thrust Vector[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(5): 170-178