摘要
以上海市老城区内某电力隧道工程为例,对8#工井所处位置周边环境进行分析,确定施工周期短、施工期间占用场地小的基坑支护结构。针对工井基坑开挖范围内软弱土层的不同加固范围及隧道工井井筒逆作和顺作两种施工工艺,利用FRWS7及PLAXIS 2D软件进行计算分析。计算结果表明:对最终开挖面以上软弱土体进行加固,可大幅度减小支护结构的变形和内力;工井井筒逆作时,临近开挖面的支撑结构承担着大部分支护结构传递来的荷载;工井井筒逆作时,基坑开挖对周边环境的影响较小。
Taking a power cable tunnel project in the old urban area of Shanghai as an example,the sur-rounding environment of the No.8 tunnel shaft was analyzed in this paper.The shaft supporting system with short construction period and less construction area was determined.For the different reinforcement areas of the soft soil layer within the shaft excavation range and the two construction techniques,top-down method and bottom-up method,software FRWS7 and PLAXIS 2D were used for calculation and analysis.The results showed that the reinforcement of the soft soil layer above the final excavation surface can significantly reduce the deformation and stress of the supporting structure.When the top-down method was used,the part of the supporting structure adjacent to the excavation surface took most of the loads transferred from the supporting structure and the shaft excavation had less impact on the surrounding environment.
作者
甄亚彬
Zhen Yabin(Shanghai Municipal Engineering Design Institute(Group)Co.,Ltd.,200092,China;Shanghai Water Design&Engineering Co.,Ltd.,200092,China)
出处
《特种结构》
2022年第4期35-40,共6页
Special Structures
关键词
老城区
隧道工井
支护结构
逆作法
Old urban area
Shaft
Support and protection structure
Top-down method
