摘要
为了在大直径盾构泥水始发段保障邻近既有地铁桥梁结构的安全性和正常营运,依托京张高铁清华园隧道3#~2#盾构区间始发段施工工程,采用有限元方法建立三维精细化数值模型,分析始发段大直径盾构掘进引起邻近桥梁结构的变形规律,并给出有针对性的防护措施。研究结果表明:在大直径盾构始发施工时,在不采取防护措施的情况下,盾构工程对邻近桥梁结构产生较大的影响;盾构掘进引起的桥梁结构水平横向位移要远大于水平纵向位移,近隧道侧的桩基和桥墩的变形均大于远隧道侧;应在盾构临近和远离2个阶段注意对邻近桥梁采取防护措施。综合运用地层加固、阻隔防护、动态监测等技术,可有效对桥梁结构进行防护,研究结果可为今后类似工程提供可靠的参考。
In order to ensure the safety and normal operation of the adjacent existing subway bridge structure in the launching section of large-diameter slurry shield tunneling,the safe tunneling in the launching section of shield is crucial.Based on the construction engineering in the launching section of the 3~2#shield section of Tsinghuayuan Tunnel of Beijing-Zhangjiakou High Speed Railway,a three-dimensional refinement numerical model was established by the finite element method.The deformation law of adjacent bridge structure caused by large-diameter shield tunneling in the launching section was analyzed,and the targeted protective measures were given.The results showed that the shield tunneling had great impact on the adjacent bridge structure without protective measures in the launching construction of large-diameter shield.The horizontal transverse displacement of bridge structure caused by shield tunneling was much higher than the horizontal longitudinal displacement,and both the deformation of pile foundation and pier near the tunnel side were higher than that at the far tunnel side,so the protective measures should be taken for adjacent bridges in two stages of shield approaching and far away.The comprehensive utilization of stratum reinforcement,barrier protection and dynamic monitoring technology can effectively protect bridge structure,which can provide reliable reference for similar projects in the future.
作者
王军
WANG Jun(China Railway 14th Bureau Group Co.,Ltd.,Jinan Shandong 250101,China)
出处
《中国安全生产科学技术》
CAS
CSCD
北大核心
2022年第4期176-184,共9页
Journal of Safety Science and Technology
基金
中国铁建股份有限公司科研课题(2018-B06)
中铁十四局集团公司科研课题(QT-2018-0016)
中铁十四局科研课题(913700001630559891202106,DDG-2019-B01,913700001630559891202110)。
关键词
大直径盾构
始发段
盾构掘进
桥梁桩基
数值模拟
变形分析
large-diameter shield
launching section
shield tunneling
bridge pile foundation
numerical simulation
deformation analysis
