Analysis of coupling characteristics between the supporting boot auxiliary tooling and surrounding rock of TBM under gradual section condition

MA Xiuquan; MIAO Chong; XIE Miao; WANG Haonan

doi:10.16579/j.issn.1001.9669.2026.07.016

Abstract：[Objective]Aiming at the problems including insufficient research on auxiliary supporting equipment under the new working condition of variable cross-section,and the failure of existing tunnel boring machine(TBM)supporting and propelling mechanisms to meet the operational requirements of such new conditions,the contact mechanical behavior between shoe auxiliary equipment and surrounding rock was analyzed,and the mechanical parameters such as comprehensive stress and comprehensive displacement of the contact zone were obtained to evaluate the stability of tooling and the overall tunneling efficiency of TBM,providing a reference for the design of engineering equipment.[Methods]Firstly,coupled contact models between shoe auxiliary tooling and surrounding rock under various supporting states were established based on the construction condition of the drainage gallery with variable cross-section at the Jinyun pumped storage power station in Zhejiang province.Secondly,the influences of tooling elongation,fitting angle between tooling shoe body and surrounding rock,contact area between tooling shoe body and surrounding rock surface,and different rock types on coupled mechanical characteristics were investigated.Finally,distribution diagrams of comprehensive stress,normal contact stress and comprehensive displacement on the contact surface between auxiliary tooling shoe body and surrounding rock were plotted,and a comparative analysis of contact-coupled mechanical characteristics between shoe auxiliary tooling shoe body and surrounding rock under different supporting states and working conditions was carried out.[Results]The results show that the distributions of comprehensive stress and normal contact stress are uneven with obvious abrupt changes when the tooling shoe body is in full contact with surrounding rock.The maximum comprehensive displacement between the two surfaces rises with the increase of the fitting angle.When the shoe body only contacts surrounding rock at the middle region,the corresponding values of comprehensive stress,normal contact stress and maximum comprehensive displacement of surrounding rock are all larger than those under full contact.With identical coupled contact parameters,the maximum comprehensive stress borne by type Ⅰ surrounding rock is higher than that of type Ⅱ and type Ⅲ surrounding rock,while its maximum comprehensive displacement is lower.The main concentration zones of comprehensive stress and comprehensive displacement of type Ⅱ and type Ⅲ surrounding rock are wider than those of type Ⅰ surrounding rock,which indicates that soft rock is more prone to yield failure and sliding deformation.