土压平衡盾构刀盘扭矩计算方法与多因素量化分析

 刀盘扭矩是设计刀盘驱动的关键参数，是设计经济型盾构、决定盾构是否高效率掘进必不可少的参数之一。以土压平衡盾构为背景，在充分理解刀盘与土体相互作用的基础上，分析影响刀盘扭矩的7个因素，并基于现场测试和理论分析分别推导出各因素的计算模型。同时，以土耳其伊兹密尔地铁和伦敦机场隧道为例，通过与实际测得的刀盘扭矩对比分析，验证理论模型的准确性，所构建的计算模型可适用于黏性土和非黏性土地层中。对各影响因素进行量化分析，分析表明刀盘各面与地层的摩擦阻力扭矩约占总扭矩的80%，其中刀盘与土体的摩擦角、刀盘直径、土体的黏着力以及土仓内的土压支撑强度都是影响刀盘扭矩大小的重要参数。

TORQUE CALCULATION METHOD OF CUTTERHEAD IN EARTH PRESSURE BALANCE SHIELD AND QUANTITATIVE ANALYSIS OF SEVERAL INFLUENCING FACTORS

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.