Deformation Characteristics and Control of Super-large Diameter Shield Tunneling Under Traffic Hub
In order to explore the construction control problem of super large diameter shield tunnel underpass the underground structure of the existing station,based on the reconstruction project of the East Sixth Ring Road of Beijing Sub-Center,the interaction between the super large diameter shield tunnel and the pile raft foundation is studied by combining the field measured data and numerical simulation.The deformation law of the underground structure raft in the process of underpass is analyzed.The accuracy of the model is verified by comparing with the field measured data,and effective construction control measures are proposed.The results show that:the displacement of the basement raft of the underground structure in the vertical direction presents a M-shaped distribution.The construction control factors that cause deformation include grouting measures,backfill layer thickness and double-line tunnel construction spacing.For this kind of underground structure,three construction control methods are mainly adopted,including the combined reinforcement and strengthening measures of synchronous grouting and post-wall grouting,the pressure of 2 m backfill layer on the roof of underground structure,and the double-line tunnel crossing the underground structure in turn,and the construction spacing is maintained at least 300 m.The combined use of these measures has achieved remarkable deformation control effect.
transportation hubsuper large diameter shieldnumerical simulationdeformation characteristicscontrol measures
NETL
NSTL
万方数据
