Mechanics Characteristic Analysis And Cluster Analysis For The Cutter Of Shield Machine

People’s demand for space is developing rapidly, so that shield machine whichis the most important tool to exploit underground has been widely used in Chinesemetro construction，the research of shield tunneling becomes more and more deeply.The cutter-head is the key part of shield machines, which is critical to the efficiencyand the service life of the whole machine. Therefore, it is of great significance toresearch on the force distribution, the main force and the torque of the cutter-head inworking condition.In order to investigate the tunneling mechanism of shield machine andvariations of cutting forces acting on the cutters, a reduced scale experimentalapparatus was developed, based on earth pressure balance shield. A cutting resistanceforce sensor was also developed, which is placed inside the cutter and can measureboth the cutting resistance force and axial resistance force. The measurementcapabilities of the apparatus are the driving load, driving torque and resistance forcesacting on the cutters. The validity of the cutter sensor which measuring the cuttingresistance force and axial resistance force without coupling between them wasdemonstrated by experiments. The experimental results indicated that the resistanceforce and axial resistance force increase linearly with the radius of the cutter-head.An excavation test was carried out in clay, silt, sand by a model earth pressurebalanced shield with a diameter of0.5m to research on the force distribution, themain force and the torque of the cutter-head in working condition. The dataacquisition system acquired the working parameters of the model EPB shield duringthe process of the test. Through the relative waveform analysis and spectrum analysisof the data, we get the stress distribution rule of the cutter-head, the variation oftorque and the pressure which are due to the cutter-head’s spinde. What is more，thispaper also try to analyze the correlation between the force distribution and thephysical properties of the soil.This paper also does research on the method of feature extraction and patternrecognition for the interaction of cutter and soil. There are six features extracted fromcutting force wave and its power spectrum. The date was divided into9categories based on the different soil in the experiments. Then the fuzzy cluster analysis withbetween-groups linkage is used to analyze it. The results show that the cluster analysiscan recognize different patterns and separate different soil. The cluster analysis alsocan evaluate the relationship which is close or distant in regard to patterns.It provide away for the recognition and monitoring of the shield machine In the actual project.