盾构刀盘系统界面载荷力学表征与近似计算模型

针对地下隧道施工重型盾构装备,提出了一种刀盘系统界面载荷的力学表征与近似计算方法.在刀盘系统与掘进界面岩土间相互作用的解耦分析基础上,引入岩土屈服破坏效应的影响,修正了掘进界面边缘区域应力集中的问题,给出了刀盘系统界面载荷沿半径方向非线性分布的规律.考虑到实际施工中的地质条件、掘进进尺、刀盘拓扑结构,以及地下埋深等因素对掘进载荷的影响,建立了刀盘系统推力与扭矩的综合分析与计算模型,实现了地质力学性能、装备掘进状态、装备结构特征3类关键因素与掘进载荷间相互影响规律的力学描述;结合天津地铁工程实例,分析与验证了界面载荷模型的有效性. 

MECHANICAL CHARACTERIZATION AND PREDICTING MODEL FOR CUTTERHEAD INTERFACE LOAD OF SHIELD MACHINE

The paper presents a mechanical characterization and predicting model for the cutterhead interface load of shield machine.The interaction between the cutterhead and the soil on the excavation interface is decoupled.The geotechnical yield effect is considered to amend the stress concentration around the edge area on the interface.Then the normal and tangential stress distributions on the cutterhead are presented.In addition,a comprehensive consideration about the interface load with the contributions of the depth burial and the cutterhead topological structure is made.The present study establishes a predicting model of the thrust and the torque acting on the cutterhead interface with the influences of geological parameters,operating parameters,and structural parameters.The effectiveness of the proposed model is verified with a metro engineering instance in China.