摘要
针对富水软弱地层条件下某城市敏感古城区,地铁建设面临的敏感环境控制难题,本文采用数值模拟方法研究了分离岛式变径盾构工法对敏感古城区的施工影响。通过建立三维有限元模型,对比分析了三种变径幅度(6.2-9.3m、6.7-9.3m、7.9-9.3m)及两种掘进顺序(先大后小/先小后大)对地表建筑物的位移及应力影响规律。研究结果表明:随着变径盾构隧道变径幅值的减小,盾构隧道对地层扰动越小;先小后大工序相较于先大后小工序地表建筑最大主应力降低34.6%,针对富水软弱地层特性,建议采用工况为7.9-9.3m变径幅度的变径盾构隧道施工方案。研究成果为类似敏感建筑物条件下,地铁建设施工提供了重要技术参考。
Aiming at the sensitive environmental control challenges faced by subway construction in a sensitive ancient urban district under water-rich soft stratum conditions,this paper employs numerical simulation methods to study the construction impact of the separated island-type variable-diameter shield tunneling method on the sensitive ancient district.A three-dimensional finite element model was established to compare and analyze the influence laws of three diameter variation ranges(6.2-9.3m,6.7-9.3m,7.9-9.3m)and two tunneling sequences(larger-first then smaller/smaller-first then larger)on the displacement and stress of surface buildings.The results show that as the diameter variation amplitude of the variable-diameter shield tunnel decreases,the disturbance to the stratum caused by shield tunneling is reduced;compared with the larger-first then smaller sequence,the maximum principal stress of surface buildings under the smaller-first then larger sequence decreases by 34.6%.Considering the characteristics of the water-rich soft stratum,the construction scheme with a diameter variation range of 7.9-9.3 m is recommended.The research findings provide an important technical reference for subway construction under similar sensitive building conditions.
作者
朱鹏霖
ZHU Penglin(China Railway SIYUAN Survey and Design Group Co.,Ltd,Wuhan 430063)
出处
《铁道勘测与设计》
2026年第1期74-78,85,共6页
Railway Survey and Design
基金
中国铁建股份有限公司科技研发计划项目(2023-B21)
苏州轨道交通科技创新研究院有限公司科研项目(KCY-04-FW-14-0003)。
关键词
分离岛式盾构隧道
变径盾构
敏感古城区
地表沉降
数值模拟
施工优化
Separated island-type shield tunneling
Variable-diameter shield
Sensitive ancient urban district
Surface settlement
Numerical simulation
Construction optimization
