INFLUENCE OF CONSTRUCTION PARAMETERS AND CROSS ANGLE ON EXISTING TUNNEL SETTLEMENT DURING UNDERCROSSING SHIELD TUNNELING CONSTRUCTION

The tunnel construction causes deformation, even damage of the nearby buildings and other types of structures. By 3D finite element method, the grouting material hardening is simulated by using the variable stiffness equivalent method, and the shield tail synchronous grouting is simulated by using the equivalent uniform grouting pressure. Then, the paper studies the influence of undercrossing shield tunneling construction on the existing tunnel settlement under different jacking forces, the shield tail grouting, the shield force, and the cross angle of tunnels. The results show that the grouting pressure and the grouting material hardening have direct influence on the existing tunnel settlement. The existing tunnel settlement decreases with the increase of the jacking force and grouting layer parameters. The existing tunnel settlement caused by shield force changes is more than that of the normal promoting. When the cross angle of tunnels is less than 90°, the existing tunnel settlement decreases with the increase of the cross angle.