摘要
针对新建盾构隧道下穿施工时,对既有上卧盾构隧道结构的扰动影响问题,应用非线性接触理论和多尺度混合建模技术,建立三维非连续精细化数值模型,重点分析隧道正交下穿施工扰动下,既有上卧盾构隧道管片与接头受力和变形规律。研究结果表明:新建隧道下穿施工诱发既有上卧盾构隧道整体下沉,表现为隧道结构竖向收敛波动和仰拱沉降显著;纵缝接头变形以张开为主,环缝接头变形以错台为主,且同一环中拱顶处变形最大;环缝接头应力集中明显,靠近交叉点处管片环缝的最大、最小应力均接近混凝土强度设计值,局部裂损风险高;受下部开挖影响,上卧盾构隧道环缝接头螺栓剪应力值增加显著。
To further understand the influence caused by construction of underline shield tunnel on the existing shield structure, a three-dimensional non-continuous refined numerical model was established by non-linear contact theory and multi-scale hybrid modeling technology. The emphases were put on the stress and deformation of segment and joint structures of existing tunnel, especially when the underline shield tunnel is passing through perpendicular to the existing one. The results show that under the construction of underline tunnel, integral sinking is observed in the existing one, which is characterized by fluctuant vertical convergence and significant settlement of inverted arch. Besides, the deformation of joints at longitudinal and circumferential seams of lining show significant opening and dislocation respectively, and the largest deformation is found in the vault. The stress concentration is obvious around the joints at circumferential seam of lining, where the maximum and minimum stress values almost reach to the design values of concrete strength nearthe intersection of two tunnels, resulting in high risk at local cracking. On the other hand, significantly increased shear stress of longitudinally connected bolt is detected during construction of underline shield tunnel.
作者
张毫毫
雷明锋
刘凌晖
李玉峰
唐钱龙
王立川
ZHANG Haohao;LEI Mingfeng;LIU Linghui;LI Yufeng;TANG Qianlong;WANG Lichuan(School of Civil Engineering,Central South University,Changsha 410075,China;Key Laboratory of Engineering Structure of Heavy Haul Railway(Central South University),Changsha,410075,China;China Construction Tunnel Construction Co.,Ltd.,Chongqing 401320,China;Jiangxi Transportation Vocational and Technical College,Nanchang 330013,China;China Railway Chengdu Group Co.,Ltd,Chengdu 610082,China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2020年第2期396-404,共9页
Journal of Railway Science and Engineering
基金
湖南省自然科学基金资助项目(2018JJ3657)
江西省教育厅科学技术研究资助项目(GJJ171292)
中建隧道科技研发课题(cscec5b-SUI-2019-02)
中国铁路成都局集团有限公司科技研究开发计划资助项目(CX1919)
关键词
盾构隧道
下穿施工
三维非连续接触模型
管片接头
shield tunnel
underpass construction
three-dimensional discontinuous contact model
segment joint