| The shield tunnelling machine is a type of complicated engineering equipment that is widely used in underground tunnel excavation and related with subjects of machinery, hydraulic, civil, control, measurement, electricity etc. Following the rapid development of the metro in our country, the demand of the shield tunneling machine is increasing. At present the shield tunneling machine used in China almost is imported, at the same time each one of the shield tunneling machine has to be designed and manufactured individually based on the different geological conditions, however the design theory and method are not mastered in our country. Based on the above reasons, it is very necessary to construct the test-bed of the shield tunnelling machine for simulating the different shield tunnelling machine works in different geological conditions and it is very meaningful to study the control method and the design theory based on the test-bed.The comprehensive test-bed is regarded as the research object in this paper. The main parameters of the test rig were determined. There are four hydraulic systems are designed including the loading system of the soil box and the cutting wheel system, the thrust system and the screw conveyor system of the simulated shield tunnelling machine. Based on the test-bed, using the AMESim software the simulation related to the cutting wheel hydraulic system was done. The content of the paper is summarized as following:In chapter 1, the history and the current research status of the shield tunnelling machine and the simulation test-bed were introduced based on lots of publications and conference papers. The comprehensive test-bed, the research object of the paper was introduced. The research significance and the content of the paper were introduced.In chapter 2, a dual-pump hydraulic system which is based on proportional relief valve was designed for soil loading box loaded, completing with soil water and soil pressure to the requirements of 0.65 MPa. In this paper, the main hydraulic system components were selected and the selections were checked. The main circuit valve block and the district valve blocks were integrated designed by the 3D software Solidworks. The 3D software was used on the loading beam design and the loading beam was checked by COSMOSXpress, the plug-in of Solidworks.In chapter 3, according to the function requirements of the test rig and the analysis of the real shield tunneling process, the parameters of the simulation shield tunneling machine, such as the cutter torque and the thrust were calculated. The three principles of the three main hydraulic systems on the simulation shield tunneling machine, including variable pump-variable motor hydraulic cutting wheel system, the district control thrust system and screw conveyor hydraulic system. In this paper, the main hydraulic system components were selected and the selections were checked.In chapter 4, the cutting wheel hydraulic systems of the foreign advanced shield tunnelling machine were introduced. From the variable pump-quantitative motor system, the mathematical models of the quantitative motor-variable pump and the variable pump-variable motor were established and the relevant parameters were analyzed.In chapter 5, the variable pump-variable motor large-scale speed closed hydraulic cutting wheel system was analyzed used the simulation software AMESim. Simulation results show that the hydraulic system meet the large-scale speed regulation and the high change torque characteristics of the cutting wheel system. Closed-loop control mode is better than open-loop control mode. In high speed and large torque condition, the scope of the speed will increase, if the stepless speed control was used in variable motor. There is little impact to the synchronization, if the volumetric efficiency of the motor decline. But if the mechanical efficiency decline, the synchronization will be influenced.In chapter 6, some conclusions are given and some new views are put forward in the future. The thrust mathematical model was established.
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