Research On Shield Tunneling Simulation System And Earth Pressure Balance Technology

Shield tunneling machine is a very complicated engineer machinery for tunneling, involving so many technologies on optical, mechanical, electronic, hydraulic, sensing, and informational fields. Shield tunneling machine not only has the functions of cutting and conveying the soils, assembling the tunnel segment, but also can be responsible for measuring, guiding, deviation rectifying. Currently a large scale of tunnel construction is carried on all over the country, whereas the civil research on shield tunneling machine is just on initial stage. Since the complex interaction rule between shield tunneling machine and complicated geological conditionals is still beyond knowledge, it is necessary to build a high level test rig of simulating the construction conditions to obtain the design technology and some other key technologies on shield tunneling machine and to improve the reliability of shield tunneling machine while tunneling.According to the demands of practicality and advancement of the test rig, the simulated geological environment consisted of load device, driving system and some other auxiliary systems is designed. Simulation of the electro-hydraulic system in shield has been designed based on the actual structural features and construction process.Considering the monitoring needs of electrohydraulic system, the monitoring system is built on the basis of PLC and LabVIEW. Through theoretical analysis, the mathematic model of the earth pressure balance control is deduced. Base on the analysis of the relationship between control parameters and earth pressure of chamber, multiple-model adaptive earth pressure balance control system is established by use of ANFIS. Furthermore, the character of the control system is tested by simulation with experimental data. The main research content of this paper is as follows:In the first chapter, the construction principle, the composition structure and the classification of the shield tunneling machine are firstly introduced, and then the historical and present development state of the shield tunneling machine is described. Moreover the established test rig on the shield tunneling machine and the research made on pressure control technology are elaborated. Finally the significance and research content of this subject is discussed.In the second chapter, the load system and the auxiliary system are firstly designed which adopt hydraulic technology to build up a simulated geological environment. Base on theoretical calculation, the load mechanism and simulation box are designed by use of Solidworks software. The structure strength of key components is analyzed with Ansys software, furthermore the load structure is optimized and then the dimension is determined. The load hydraulic system is designed and the parameter calculation and component selection are accomplished finally.In the third chapter, the structure of the shield tunneling machine is designed with the method of module design at first. Then the electrohydraulic system of the shield tunneling machine mainly consisted of cutter head driving system, thrust and hinge system, screw conveyor system, segment erection system is established, meanwhile the auxiliary systems such as slurry load system, etc are designed.In the forth chapter, firstly the hardware and software structure of the test rig monitoring system is designed according to the monitoring demands. The interface design, control strategy and programming mode of PLC system which adopt Profibus-DP bus technology are then introduced. The man-machine interface and data manage system are designed by use of LabVIEW software. Finally, the design feature of the monitoring interface and the communication with upper machine and the development of database and control arithmetic are illustrated.In the fifth chapter, the mathematic model of the earth pressure balance control system is built up. The relationship between thrust force, penetration rate, screw conveyor speed and earth pressure is analyzed theoretically. The earth pressure balance control system in a certain strata is established by use of ANFIS inferring system, and the earth pressure balance control system is essentially designed under various complicated geological situation with multiple-model control technology. By use of experimental data from three typical strata, the character of two different control strategies which are switching and weighting control strategies is researched respectively. The results show that multiple-model control system with ANFIS controller can achieve a good performance under different complicated geological conditions.