小曲率盾构隧道管片施工附加内力计算模型研究

Calculation model of additional internal force of shield tunnel with small curvature during construction stage

由于盾构隧道施工阶段结构受力复杂,尤其是对于小曲率盾构隧道,千斤顶推力容易引起较大的附加弯矩。为了解决小曲率盾构隧道附加内力计算问题,以某地电缆隧道盾构施工工程为背景,对千斤顶推力进行简化分析,提出了千斤顶推力引起的附加弯矩计算公式。根据公式计算结果,附加弯矩随盾构机的外径和长度增大而增大,随盾构隧道转弯半径减小而增大。针对该工程项目的具体结构尺寸对千斤顶推力的设置提供建议,计算结果可为类似工程提供一定的参考。

Due to the complex structure stress during shield tunnel construction stage,especially for shield tunnel with small curvature,large additional bending moment is caused by the jack thrust.Based on the construction project of a cable shield tunnel,the jack thrust was simplified and the calculation formula of additional bending moment caused by jack thrust was proposed.According to the calculation results of the formula,the additional bending moment increased with the increase of the outer diameter and length of the shield machine,and the bending moment increased with the decrease of the turning radius of the shield tunnel.The setting of jack thrust was suggested according to the specific structure size of the project.The calculation results could provide some reference for similar projects.