Accurate method for predicting vertical displacement of adjacent tunnel by foundation pit excavation

The invention discloses an accurate method for predicting vertical displacement of an adjacent tunnel during excavation of a foundation pit. The method comprises the following steps: (1) determining profile parameters of the foundation pit and the tunnel, tunnel rigidity and physical and mechanical parameters of a soil body; (2) determining a stress mode and a model sketch of the tunnel; (3) determining the additional stress of the tunnel, and establishing a stress-strain equation about the lower layer spring w2 of the tunnel; (4) solving the stress-strain equation based on a difference method and boundary conditions of the tunnel to obtain lower-layer spring w2 matrix analysis; (5) obtaining an expression of w and a bending moment and shearing force expression of the tunnel according to a relational expression of the vertical total displacement w of the tunnel and the lower-layer spring w2. According to the accurate method for predicting the vertical displacement of the adjacent tunnel during foundation pit