Study on the Influence Factors of Excavation Face Stability of Large Section Box Culvert Under the Action of Pipe Curtain
The stability of excavation face of large-section box culvert under the action of pipe curtain is affected by various construction conditions,which is necessary to carry out systematic research on its influencing factors.Based on the shallow buried tunnel section of Luzhou Avenue in Hefei Binhu Science City,this paper constructs a large-scale three-dimensional refined numerical model to analyze the stability law of excavation face under the influence of factors such as steel pipe curtain group,support pressure,jacking distance,excavation method and pipe curtain stagnation distance.The results show that:(1)the steel pipe curtain group plays an important role in maintaining the stability of the excavation face,and the unconnected pipe curtain structure is more conducive to maintaining the stability of the excavation face.(2)When the support pressure is less than 80 kPa,the displacement of the longitudinal axis of the excavation face gradually decreases with the increase of the support pressure,and gradually tends to be stable.When the support pressure is greater than 90 kPa,the excavation face state is easy to be inverted 'S'shape.(3)The construction method of excavating from both sides first and then excavating in the middle is conducive to maintaining the stability of the excavation face.(4)With the increase of the stagnation distance of the pipe curtain,the outward displacement of the longitudinal axis of the excavation face gradually increases,which is not conducive to stability.
pipe roof box culvert construction methodexcavation face stabilityinfluencing factornumerical simulation
NETL
NSTL
万方数据
