Inversion analysis of service performance of shield tunnel: Driven by 3D laser scanning data and analytical models

Massive detection data of tunnel inner contour dimensions can be acquired using 3D laser scanning technology. However, current researches have not yet determined the structural performance status based on the tunnel detection data. This paper investigated the service performance of shield tunnel based on the 3D laser scanning data and analytical models. The fusion method between analytical models and detection data was verified by the structural deformations. Among them, the structural features, the compatible deformation between segments and joints, and the nonlinear bending stiffness of the joints are simultaneously considered in the analytical models. For the detection data, the structural deformations of the shield tunnel were obtained through the 3D laser scanner. The reliability of the calculation results was assessed by the correlation coefficient between the detection deformations and the analytical deformations. The results indicate that the physical interpretation of the proposed models can be enhanced by incorporating the physical constraints and geological information. And the reliability of the analytical results depends on the deformation data of the segment structure. In addition, the geological resistance occurs when the horizontal displacement of the segment structure exceeds a threshold value. It is noteworthy that even if the ellipticity of the segment ring is identical, the segment structure may still bear different external loads, and the structural internal forces may also be different. The integration of the analytical methods with the cutting-edge detection techniques is expected to advance the quantitative and reliable assessment for the service performance status of the shield tunnel.