摘要
以南京地铁3号线越江隧道为依托,通过对大直径越江盾构隧道3环管片周边荷载、钢筋应力进行监测,并对实测数据进行统计分析,探讨越江盾构隧道施工期以及施工后一段时间,盾构隧道荷载、受力变化特征,并根据现场实测应力计算盾构管片内力,采用修正惯用法和梁-弹簧法计算隧道衬砌内力,并与实测值进行比较。研究结果表明:盾构掘进过程会引起管片周边土体的扰动,管片壁后注浆及施工期的临时荷载会影响管片周边土压力分布及大小;管片内外侧钢筋应力变化规律与实测土压力变化趋势基本一致,管片实测应力开始趋于稳定时间相比实测土压力较短;梁-弹簧法计算管片内力与实测反算结果更吻合,实测反算轴力是计算轴力的2倍左右。研究成果可为大直径盾构越江隧道管片设计、施工提供参考。
Based on the Nanjing Metro Line 3 cross-river tunnel, the load and reinforcement stress of the 3 loop tubes was monitored by cross-river shield tunnel with large diameter, and the measured data were statistically analyzed. To explore cross-river shield tunnel during the construction and after construction for a period of time, load, the stress variation characteristics of shield tunnel, and internal forces of shield segments were calculated based on the field measured stresses. The uniform rigidity ring method and beam-spring method were used to calculate the internal force of tunnel lining, and compared with the measured value. The results show that the process of shield tunneling will cause the disturbance of the soil around the segment, the grouting behind the wall of the segment and the temporary load during the construction period will affect the distribution and value of the earth pressure around the segment. The change law of steel stress inside and outside the segment is basically consistent with the changing trend of measured earth pressure. The measured stress of the segment is shorter than the earth pressure to reach stable state. The internal force of the cross section of segment calculated by the beam-spring method is close to the measured result, and the back-calculation results are approximately twice as much as the axial forces of segments calculated. The results can provide reference for the design and construction of shield tunnel with similar condition.
作者
李雪
张玉申
耿翱鹏
耿凤娟
吴九七
Li Xue;Zhang Yushen;Geng Aopeng;Geng Fengjuan;Wu Jiuqi(School of Geoscience and Technology,Southuest Petroleum University,Chengdu 610500,P.R.China;Shanghai Key Laboralory of Rail Infrastructue Durability and System Safety,Tongji Uniersity,Shanghai 201804,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2022年第1期297-304,共8页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(51808469)
上海市轨道交通结构耐久与系统安全重点实验室开放基金(R201902)。
关键词
大直径盾构
越江隧道
现场实测
土压力
large diameter shield
cross-river tunnel
field measurement
earth pressure
