TORQUE CALCULATION METHOD OF CUTTERHEAD IN EARTH PRESSURE BALANCE SHIELD AND QUANTITATIVE ANALYSIS OF SEVERAL INFLUENCING FACTORS
LI Chao1,2,ZHOU Hongwei1,ZUO Jianping1,DING Jingyang1,GAO Mingzhong3,QI Shuai1
(1. State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology,Beijing 100083,China;2. Department of Applied Earth Sciences,Technical University of Berlin,Berlin D–10623,Germany;3. College of Water Resources and Hydropower,Sichuan University,Chengdu,Sichuan 610065,China)
Abstract:The torque of cutterhead plays an important role in the design of the drive system and economic design of the tunnel boring machine,which is also one of the essential parameters determining the efficiency of the tunnel boring machine. Based on the earth pressure balance shield,seven influential factors on torque have been analyzed in the full understanding of the interaction between cutting wheel and the soil. What?s more,the calculation model with each factor is proposed combining the field project and the theoretical analysis. In comparison to the actual torque of the tunnel projects in Izmir Metro and London Airport,it is indicated that the theoretical model is suitable for cohesive and non-cohesive soil layers. By quantitative analysis,it is shown that 80% of the total torque overcomes the friction loss of the cutterhead surfaces;and the skin friction angle,radius of the cutterhead,adhesion of soil and earth support pressure are important parameters in determining the torque.