Analysis of Effect of Space Position on Stack Shield Tunnel Construction
In the face of the complex construction form and the condition of water-rich sand layer in the overlapping section,it is urgent to explore the response law of formation displacement and lining deformation to reduce potential construction risks.In this study,based on practical projects,aiming at the interaction between the upper line shield tunnel and the existing lower line tunnel during post-construction,the finite element numerical simulation method was adopted,combined with field monitoring data and formation conditions,and factors affecting the spatial position such as tunnel connection inclination angle and tunnel spacing were taken into account to analyze the change law of formation settlement and lining stress and strain and the interaction mechanism during shield tunneling.The corresponding construction protection measures are proposed.The results show that the position relation of the overlaid tunnel has a significant influence on the formation and lining.With the increase of the inclination Angle of the tunnel center line,the peak position of the surface settlement shifts,and the settlement reaches the minimum value when the inclination is about 45°,and the arch bottom and arch waist of the downline tunnel have the largest deformation.As the distance between two completely stacked tunnels decreases,the interaction effect increases.
万方数据
维普
