小曲率半径盾构隧道施工中辅助油缸千斤顶推力计算模型研究

Research on Thrust Calculation Model of Auxiliary Oil Cylinder Jack in Small Curvature Radius Shield Tunneling

在小曲率半径隧道盾构掘进施工时,千斤顶推力的作用会导致管片发生偏移和错台,从而引发安全事故的产生。为有效解决小曲率半径盾构隧道施工过程中由于千斤顶推力而对管片造成的不利影响,通过分析双模盾构机的掘进模式,建立了盾构隧道在掘进开挖过程中的辅推油缸千斤顶推力的计算模型,并将其应用于工程实践,对千斤顶推力进行计算分析,提出了减少或避免千斤顶推力对管片造成的不利影响的相关措施。研究结果表明:(1)双模盾构施工过程中,不同施工区间的辅推油缸千斤顶推力的取值有所不同,应根据工程实际情况确定该推力值。(2)单模盾构施工过程中,辅推油缸千斤顶推力随着贯入度的增大而增大,且增大速率呈逐渐减小的趋势。(3)提出依次从施工纠偏、管片拼装控制、掘进参数合理选取、盾构机姿态控制、盾构机推力控制、隧道纵向刚度的设置和管片质量等来控制和减小千斤顶推力对管片造成的不利影响,保证盾构施工的安全性,为类似工程的建设提供理论指导和参考。

During the shield tunneling with small curvature radius,due to the role of jack thrust,the segments will shift and stagger,which will lead to the safety accidents.In order to effectively solve the adverse impact of jack thrust on the segment during the construction of shield tunnel with small curvature radius,the tunneling mode of double-mode shield tunneling machine is analyzed.The calculation model of the thrust of the auxiliary oil cylinder jack in the shield tunneling process for the shield tunnel is established.And the model is applied in the engineering practice.The jack thrust is calculated and analyzed.The relevant measures to reduce or avoid the adverse effects of the jack thrust on the segment are proposed.The results show that during the construction of double-mode shield machine,the value of the thrust of the auxiliary oil cylinder jack in the different construction sections is different,and the thrust value should be determined according to the actual situation of the project.During the construction of single-mode shield machine,the thrust of the auxiliary oil cylinder jack increases with the increase of penetration,and the increasing rate gradually shows a decreasing trend.It is proposed to control and reduce the adverse impact of the jack thrust on the segment from the construction correction,segment assembly control,reasonable selection of tunneling parameters,shield machine attitude control,shield machine thrust control,setting of tunnel longitudinal stiffness and segment quality so as to ensure the safety of shield construction and provide the theoretical guidance and reference for the construction of similar projects.