考虑横向性能的盾构隧道纵向非线性等效抗弯刚度计算模型  

Calculation model of longitudinal nonlinear equivalent bending stiffness of shield tunnel considering its transverse performance

作　　者：王祖贤 施成华[1] 龚琛杰 曹成勇 彭铸 孙影杰 WANG Zu-xian;SHI Cheng-hua;GONG Chen-jie;CAO Cheng-yong;PENG Zhu;SUN Ying-jie(School of Civil Engineering,Central South University,Changsha,Hunan 410075,China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen,Guangdong 518060,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]深圳大学土木与交通工程学院,广东深圳518060

出　　处：《岩土力学》2023年第5期1295-1308,共14页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.51778636,No.51908557);湖南省自然科学基金资助项目(No.2021JJ30837)。

摘　　要：纵向等效抗弯刚度是采用等效连续化模型进行盾构隧道纵向结构分析的关键参数,其在纵向轴力和弯矩耦合作用下具有明显的非线性特征。在既有盾构隧道非线性抗弯刚度理论的基础上,考虑盾构隧道的横向变形特征,建立考虑盾构隧道横向性能的纵向非线性等效抗弯刚度计算模型,基于椭圆积分严格推导纵向轴力和弯矩耦合作用下盾构隧道在环缝完全闭合、半张开和完全张开3种变形模式下的纵向等效抗弯刚度,并根据中性轴位置方程得到各弯曲模式的临界轴力和弯矩判据,通过与既有解析模型计算结果、模型试验数据和数值计算结果的对比验证了所提出的模型的可靠性。采用该模型开展了纵向轴力和弯矩耦合作用下盾构隧道横向性能对其纵向刚度的影响分析,讨论了理论模型构建时非严格椭圆积分推导的计算误差,并基于该模型提出了附加荷载作用下盾构隧道横纵向变形的耦合分析方法。研究结果表明:该模型的解析推导是准确可靠的;盾构隧道的纵向等效抗弯刚度与其横向刚度密切相关,且为正相关;在压弯状态下盾构隧道纵向等效抗弯刚度随横向刚度的增大而得到明显提升。提出的模型构建了轴力和弯矩耦合作用下盾构隧道横、纵向刚度的匹配性,为盾构隧道横、纵向结构耦合分析搭建了桥梁。The longitudinal equivalent bending stiffness(LEBS) of the shield tunnel is a key parameter when the longitudinal structural analyses of the shield tunnel are conducted by the equivalent continuous model.There will be a significantly nonlinear characteristics on the LBSE if the longitudinal axial force and the bending moment are loaded simultaneously.In this paper,based on the existing theories of the nonlinear bending stiffness of the shield tunnel,a calculation model of the longitudinal nonlinear equivalent bending stiffness of the shield tunnel incorporating its transverse performance has been proposed where the transverse deformation characteristics are considered.The LEBSs of the shield tunnel are derived strictly based on the elliptical integral when the circumferential joint of the shield is closed completely,semi open,and open fully respectively due to the coupling action of the longitudinal axial force and bending moment.The criteria of the critical axial force and the critical bending moment to distinguish the three bending modes are deduced with the equations about the neutral axial position.Then the reliability of the proposed model is validated via the results calculated by the existing analytical model,the model test data and the numerical results.After that,the analyses of the influences of the transverse performance of the shield tunnel on its longitudinal stiffness are carried out using the verified model when the shield tunnel suffers the coupling action of the longitudinal axial force and bending moment.Finally,the calculation errors of the simplified deductions are discussed.In addition,a coupled analysis method for the transverse and longitudinal deformations of a shield tunnel induced by additional load is developed based on the established analytical model.The results show that the analytical derivations of the proposed model are accurate and reliable.The LEBS of the shield tunnel is closely related to its transverse stiffness,and there is a positive correlation between the two.The LEBS of

关 键 词：盾构隧道 纵向连续化模型 横向性能 轴力弯矩耦合作用 纵向非线性等效抗弯刚度 

分 类 号：TU451[建筑科学—岩土工程]