Deformation analysis and control of a running subway crossed by upper- and lower-shield in succession

Based on a close crossing project in Shanghai metro construction, in which shield crosses from below and above a running subway tunnel successively, the deformation of the subway tunnel and the disturbance to the surrounding environment caused by different crossing sequences are comparatively analyzed by means of numerical modelling methods. The results show that the diversification of the displacement fields caused by the close crossing is very complex. Further analysis is performed. The sequence of lower-crossing first and then upper-crossing is more favorable to the deformation and disturbance control, and a series of controlling measures for the diversification are formulated. Finally, based on the monitoring data, the rationality of theoretical predictions and construction measures is verified. It will provide a reference for similar projects.