Construction Scheme and Influence Analysis of Shallow-Buried Large Diameter Steel Pipe Curtain

［Objective］The construction of shallow-buried pipe curtain structure may disturb the stratum and cause ground deformation. Therefore, it is necessary to study the influence of pipe curtain structure jacking sequence on land subsidence in order to reduce the disturbance of soft soil stratum caused by the jacking of pipe curtain groups. ［Method］Taking the shallow-buried tunnel section of Luzhou Avenue in Hefei City as an example, the land subsidence caused by steel pipe curtain jacking construction is monitored; combined with the finite difference model, the influence of the steel pipe curtain jacking sequence on land subsidence is analyzed. Based on the monitoring data, the actual jacking conditions and the finite difference model, the differential effects of different steel pipe curtain jacking construction schemes on ground deformation are analyzed, and the steel pipe jacking sequence is optimized. ［Result & Conclusion］Compared with steel pipes of the upper row, the jacking construction of the lower row steel pipes has a greater impact on land subsidence. Therefore, the jacking construction scheme for the overall steel pipe curtain should first jack the upper row of steel pipes, then the vertical steel pipes on both sides, and finally the lower row of steel pipes; while the jacking construction of the transverse steel pipes should start from the middle, and then jack the steel pipes alternately in sequence; the vertical steel pipes on both sides should be jacked from top to bottom, and the steel pipes at the same level should be jacked simultaneously.